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      "dateAssigned": "2026-10-26T09:42:31.000Z",
      "datePublic": "2026-10-25T00:00:00.000Z",
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              "value": "\u003cp\u003eAllocation of Resources Without Limits or Throttling vulnerability in \u003ccode\u003ehackney_conn\u003c/code\u003e in benoitc hackney allows a malicious HTTP server to exhaust client memory via an oversized or highly compressed response body. \u003ccode\u003ehackney:request/5\u003c/code\u003e and \u003ccode\u003ehackney:body/1\u003c/code\u003e return the whole response body, and nothing bounds how much the connection process buffers. Any server the client requests can trigger it.\u003c/p\u003e\n\u003cp\u003e\u003ccode\u003ehackney_conn:read_full_body/2\u003c/code\u003e and the HTTP/2 and HTTP/3 accumulators append every chunk until the body ends. With \u003ccode\u003e{auto_decompress, true}\u003c/code\u003e the buffered body is then inflated in one step with \u003ccode\u003ezlib:gunzip/1\u003c/code\u003e or \u003ccode\u003ezlib:inflate/2\u003c/code\u003e, which return the whole output at once.\u003c/p\u003e\n\u003cp\u003eThis issue affects hackney: from 2.0.0-beta.1 before 4.9.0.\u003c/p\u003e"
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              "value": "Allocation of Resources Without Limits or Throttling vulnerability in `hackney_conn` in benoitc hackney allows a malicious HTTP server to exhaust client memory via an oversized or highly compressed response body. `hackney:request/5` and `hackney:body/1` return the whole response body, and nothing bounds how much the connection process buffers. Any server the client requests can trigger it.\n\n`hackney_conn:read_full_body/2` and the HTTP/2 and HTTP/3 accumulators append every chunk until the body ends. With `{auto_decompress, true}` the buffered body is then inflated in one step with `zlib:gunzip/1` or `zlib:inflate/2`, which return the whole output at once.\n\nThis issue affects hackney: from 2.0.0-beta.1 before 4.9.0."
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      "references": [
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          "name": "hackney 4.9.0 release notes",
          "tags": [
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          "url": "https://github.com/benoitc/hackney/releases/tag/4.9.0"
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          "url": "https://cna.erlef.org/cves/CVE-2026-97200.html"
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          "url": "https://osv.dev/vulnerability/EEF-CVE-2026-97200"
        },
        {
          "name": "Cap buffered response bodies with max_body_size and bound decompression (benoitc/hackney#980)",
          "tags": [
            "related"
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          "url": "https://github.com/benoitc/hackney/pull/980"
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          "name": "Introducing commit dc41b79 in benoitc/hackney",
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      "source": {
        "discovery": "EXTERNAL"
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      "title": "Unbounded response body buffering and decompression in hackney",
      "workarounds": [
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          "lang": "en",
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              "value": "\u003cp\u003eLeave \u003ccode\u003eauto_decompress\u003c/code\u003e disabled (the default). Without it \u003ccode\u003ehackney_conn:maybe_decompress_body/2\u003c/code\u003e never inflates the body, which closes the amplification half. The uncapped raw body read has no workaround.\u003c/p\u003e"
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              "type": "text/markdown",
              "value": "Leave `auto_decompress` disabled (the default). Without it `hackney_conn:maybe_decompress_body/2` never inflates the body, which closes the amplification half. The uncapped raw body read has no workaround."
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          "value": "Leave auto_decompress disabled (the default). Without it hackney_conn:maybe_decompress_body/2 never inflates the body, which closes the amplification half. The uncapped raw body read has no workaround."
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              "value": "\u003col\u003e\n\u003cli\u003eBuild a gzip stream whose inflated size is 1 GB from a reused 64 KB chunk of zero bytes (deflate with window bits 31, best compression). The stream is about 1 MB on the wire.\u003c/li\u003e\n\u003cli\u003eStart a TCP listener on loopback that accepts one connection, reads the request, and answers \u003ccode\u003eHTTP/1.1 200 OK\u003c/code\u003e with \u003ccode\u003eContent-Encoding: gzip\u003c/code\u003e, a \u003ccode\u003eContent-Length\u003c/code\u003e matching the stream, \u003ccode\u003eConnection: close\u003c/code\u003e, and the stream as body.\u003c/li\u003e\n\u003cli\u003eFrom a node running a vulnerable hackney, call \u003ccode\u003ehackney:request(get, Url, [], \u0026lt;\u0026lt;\u0026gt;\u0026gt;, [{auto_decompress, true}, with_body])\u003c/code\u003e against that listener.\u003c/li\u003e\n\u003cli\u003eObserve the returned body of 1,048,576,000 bytes and the VM memory growing by about 1.8 GB for a 1,019,197 byte response. A larger stream, or an endless body without \u003ccode\u003eauto_decompress\u003c/code\u003e, drives the node out of memory.\u003c/li\u003e\n\u003c/ol\u003e"
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              "value": "1. Build a gzip stream whose inflated size is 1 GB from a reused 64 KB chunk of zero bytes (deflate with window bits 31, best compression). The stream is about 1 MB on the wire.\n2. Start a TCP listener on loopback that accepts one connection, reads the request, and answers `HTTP/1.1 200 OK` with `Content-Encoding: gzip`, a `Content-Length` matching the stream, `Connection: close`, and the stream as body.\n3. From a node running a vulnerable hackney, call `hackney:request(get, Url, [], \u003c\u003c\u003e\u003e, [{auto_decompress, true}, with_body])` against that listener.\n4. Observe the returned body of 1,048,576,000 bytes and the VM memory growing by about 1.8 GB for a 1,019,197 byte response. A larger stream, or an endless body without `auto_decompress`, drives the node out of memory."
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          ],
          "value": "* Build a gzip stream whose inflated size is 1 GB from a reused 64 KB chunk of zero bytes (deflate with window bits 31, best compression). The stream is about 1 MB on the wire.\n* Start a TCP listener on loopback that accepts one connection, reads the request, and answers HTTP/1.1 200 OK with Content-Encoding: gzip, a Content-Length matching the stream, Connection: close, and the stream as body.\n* From a node running a vulnerable hackney, call hackney:request(get, Url, [], \u003c\u003c\u003e\u003e, [{auto_decompress, true}, with_body]) against that listener.\n* Observe the returned body of 1,048,576,000 bytes and the VM memory growing by about 1.8 GB for a 1,019,197 byte response. A larger stream, or an endless body without auto_decompress, drives the node out of memory."
        }
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              "value": "\u003cp\u003e\u003cstrong\u003e1. Unbounded accumulation.\u003c/strong\u003e \u003ccode\u003ehackney:request/5\u003c/code\u003e with a body, and \u003ccode\u003ehackney:body/1\u003c/code\u003e after \u003ccode\u003estart_response/1\u003c/code\u003e, read the response in \u003ccode\u003esrc/hackney_conn.erl\u003c/code\u003e through \u003ccode\u003eread_full_body/2\u003c/code\u003e, which appends each chunk to a binary accumulator until the body ends. The HTTP/2 and HTTP/3 synchronous paths accumulate stream data the same way. No option caps the size.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003e2. One-step decompression.\u003c/strong\u003e With \u003ccode\u003e{auto_decompress, true}\u003c/code\u003e hackney sends \u003ccode\u003eAccept-Encoding: gzip, deflate\u003c/code\u003e. Once the body is complete, \u003ccode\u003emaybe_decompress_body/2\u003c/code\u003e dispatches on \u003ccode\u003eContent-Encoding\u003c/code\u003e to \u003ccode\u003edecompress_gzip/1\u003c/code\u003e (\u003ccode\u003ezlib:gunzip/1\u003c/code\u003e) or \u003ccode\u003edecompress_deflate/1\u003c/code\u003e (\u003ccode\u003ezlib:inflate/2\u003c/code\u003e). Both return the whole output at once, so the inflated size is bounded only by the compression ratio. The report measured a 1 MB gzip body inflating to 1 GB on hackney 4.8.4.\u003c/p\u003e"
            },
            {
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              "type": "text/markdown",
              "value": "**1. Unbounded accumulation.** `hackney:request/5` with a body, and `hackney:body/1` after `start_response/1`, read the response in `src/hackney_conn.erl` through `read_full_body/2`, which appends each chunk to a binary accumulator until the body ends. The HTTP/2 and HTTP/3 synchronous paths accumulate stream data the same way. No option caps the size.\n\n**2. One-step decompression.** With `{auto_decompress, true}` hackney sends `Accept-Encoding: gzip, deflate`. Once the body is complete, `maybe_decompress_body/2` dispatches on `Content-Encoding` to `decompress_gzip/1` (`zlib:gunzip/1`) or `decompress_deflate/1` (`zlib:inflate/2`). Both return the whole output at once, so the inflated size is bounded only by the compression ratio. The report measured a 1 MB gzip body inflating to 1 GB on hackney 4.8.4."
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          "value": "1. Unbounded accumulation. hackney:request/5 with a body, and hackney:body/1 after start_response/1, read the response in src/hackney_conn.erl through read_full_body/2, which appends each chunk to a binary accumulator until the body ends. The HTTP/2 and HTTP/3 synchronous paths accumulate stream data the same way. No option caps the size.\n\n2. One-step decompression. With {auto_decompress, true} hackney sends Accept-Encoding: gzip, deflate. Once the body is complete, maybe_decompress_body/2 dispatches on Content-Encoding to decompress_gzip/1 (zlib:gunzip/1) or decompress_deflate/1 (zlib:inflate/2). Both return the whole output at once, so the inflated size is bounded only by the compression ratio. The report measured a 1 MB gzip body inflating to 1 GB on hackney 4.8.4."
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    "datePublished": "2026-10-26T13:49:40.392Z",
    "dateReserved": "2026-10-26T05:15:01.465Z",
    "dateUpdated": "2026-10-26T15:35:50.487Z",
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\"NOT_DEFINED\", \"version\": \"4.0\", \"Recovery\": \"NOT_DEFINED\", \"baseScore\": 8.2, \"Automatable\": \"NOT_DEFINED\", \"attackVector\": \"NETWORK\", \"baseSeverity\": \"HIGH\", \"valueDensity\": \"NOT_DEFINED\", \"vectorString\": \"CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N\", \"providerUrgency\": \"NOT_DEFINED\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"HIGH\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\", \"vulnerabilityResponseEffort\": \"NOT_DEFINED\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"cpes\": [\"cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*\"], \"repo\": \"https://github.com/benoitc/hackney\", \"vendor\": \"benoitc\", \"modules\": [\"hackney_conn\", \"hackney\"], \"product\": \"hackney\", \"versions\": [{\"status\": \"affected\", \"version\": \"2.0.0-beta.1\", \"lessThan\": \"4.9.0\", \"versionType\": \"semver\"}], \"packageURL\": \"pkg:hex/hackney\", \"packageName\": \"hackney\", \"programFiles\": [\"src/hackney_conn.erl\", \"src/hackney.erl\"], \"collectionURL\": \"https://repo.hex.pm\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"hackney_conn:read_full_body/2\"}, {\"name\": \"hackney_conn:maybe_decompress_body/2\"}, {\"name\": \"hackney_conn:decompress_gzip/1\"}, {\"name\": \"hackney_conn:decompress_deflate/1\"}, {\"name\": \"hackney:request/5\"}, {\"name\": \"hackney:body/1\"}]}, {\"cpes\": [\"cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*\"], \"repo\": \"https://github.com/benoitc/hackney\", \"vendor\": \"benoitc\", \"modules\": [\"hackney_conn\", \"hackney\"], \"product\": \"hackney\", \"versions\": [{\"status\": \"affected\", \"version\": \"dc41b79339ca0c41e16d3f2dd17172bc2de855d6\", \"lessThan\": \"493e8bf83a391548e5101792276ab3fc428fa76c\", \"versionType\": \"git\"}], \"packageURL\": \"pkg:github/benoitc/hackney\", \"packageName\": \"benoitc/hackney\", \"programFiles\": [\"src/hackney_conn.erl\", \"src/hackney.erl\"], \"collectionURL\": \"https://github.com\", \"defaultStatus\": \"unaffected\", \"programRoutines\": [{\"name\": \"hackney_conn:read_full_body/2\"}, {\"name\": \"hackney_conn:maybe_decompress_body/2\"}, {\"name\": \"hackney_conn:decompress_gzip/1\"}, {\"name\": \"hackney_conn:decompress_deflate/1\"}, {\"name\": \"hackney:request/5\"}, {\"name\": \"hackney:body/1\"}]}], \"datePublic\": \"2026-10-25T00:00:00.000Z\", \"references\": [{\"url\": \"https://github.com/benoitc/hackney/releases/tag/4.9.0\", \"name\": \"hackney 4.9.0 release notes\", \"tags\": [\"vendor-advisory\", \"related\"]}, {\"url\": \"https://cna.erlef.org/cves/CVE-2026-97200.html\", \"name\": \"EEF CNA record for CVE-2026-97200\", \"tags\": [\"related\"]}, {\"url\": \"https://osv.dev/vulnerability/EEF-CVE-2026-97200\", \"name\": \"OSV record EEF-CVE-2026-97200\", \"tags\": [\"related\"]}, {\"url\": \"https://github.com/benoitc/hackney/pull/980\", \"name\": \"Cap buffered response bodies with max_body_size and bound decompression (benoitc/hackney#980)\", \"tags\": [\"related\"]}, {\"url\": \"https://github.com/benoitc/hackney/commit/dc41b79339ca0c41e16d3f2dd17172bc2de855d6\", \"name\": \"Introducing commit dc41b79 in benoitc/hackney\", \"tags\": [\"related\"]}, {\"url\": \"https://github.com/benoitc/hackney/commit/493e8bf83a391548e5101792276ab3fc428fa76c\", \"name\": \"Fix commit 493e8bf in benoitc/hackney\", \"tags\": [\"patch\"]}], \"workarounds\": [{\"lang\": \"en\", \"value\": \"Leave auto_decompress disabled (the default). Without it hackney_conn:maybe_decompress_body/2 never inflates the body, which closes the amplification half. The uncapped raw body read has no workaround.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003eLeave \u003ccode\u003eauto_decompress\u003c/code\u003e disabled (the default). Without it \u003ccode\u003ehackney_conn:maybe_decompress_body/2\u003c/code\u003e never inflates the body, which closes the amplification half. The uncapped raw body read has no workaround.\u003c/p\u003e\", \"base64\": false}, {\"type\": \"text/markdown\", \"value\": \"Leave `auto_decompress` disabled (the default). Without it `hackney_conn:maybe_decompress_body/2` never inflates the body, which closes the amplification half. The uncapped raw body read has no workaround.\", \"base64\": false}]}], \"dateAssigned\": \"2026-10-26T09:42:31.000Z\", \"descriptions\": [{\"lang\": \"en\", \"value\": \"Allocation of Resources Without Limits or Throttling vulnerability in hackney_conn in benoitc hackney allows a malicious HTTP server to exhaust client memory via an oversized or highly compressed response body. hackney:request/5 and hackney:body/1 return the whole response body, and nothing bounds how much the connection process buffers. Any server the client requests can trigger it.\\n\\nhackney_conn:read_full_body/2 and the HTTP/2 and HTTP/3 accumulators append every chunk until the body ends. With {auto_decompress, true} the buffered body is then inflated in one step with zlib:gunzip/1 or zlib:inflate/2, which return the whole output at once.\\n\\nThis issue affects hackney: from 2.0.0-beta.1 before 4.9.0.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003eAllocation of Resources Without Limits or Throttling vulnerability in \u003ccode\u003ehackney_conn\u003c/code\u003e in benoitc hackney allows a malicious HTTP server to exhaust client memory via an oversized or highly compressed response body. \u003ccode\u003ehackney:request/5\u003c/code\u003e and \u003ccode\u003ehackney:body/1\u003c/code\u003e return the whole response body, and nothing bounds how much the connection process buffers. Any server the client requests can trigger it.\u003c/p\u003e\\n\u003cp\u003e\u003ccode\u003ehackney_conn:read_full_body/2\u003c/code\u003e and the HTTP/2 and HTTP/3 accumulators append every chunk until the body ends. With \u003ccode\u003e{auto_decompress, true}\u003c/code\u003e the buffered body is then inflated in one step with \u003ccode\u003ezlib:gunzip/1\u003c/code\u003e or \u003ccode\u003ezlib:inflate/2\u003c/code\u003e, which return the whole output at once.\u003c/p\u003e\\n\u003cp\u003eThis issue affects hackney: from 2.0.0-beta.1 before 4.9.0.\u003c/p\u003e\", \"base64\": false}, {\"type\": \"text/markdown\", \"value\": \"Allocation of Resources Without Limits or Throttling vulnerability in `hackney_conn` in benoitc hackney allows a malicious HTTP server to exhaust client memory via an oversized or highly compressed response body. `hackney:request/5` and `hackney:body/1` return the whole response body, and nothing bounds how much the connection process buffers. Any server the client requests can trigger it.\\n\\n`hackney_conn:read_full_body/2` and the HTTP/2 and HTTP/3 accumulators append every chunk until the body ends. With `{auto_decompress, true}` the buffered body is then inflated in one step with `zlib:gunzip/1` or `zlib:inflate/2`, which return the whole output at once.\\n\\nThis issue affects hackney: from 2.0.0-beta.1 before 4.9.0.\", \"base64\": false}]}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-409\", \"description\": \"CWE-409 Improper Handling of Highly Compressed Data (Data Amplification)\"}]}, {\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-770\", \"description\": \"CWE-770 Allocation of Resources Without Limits or Throttling\"}]}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:a:benoitc:hackney:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"4.9.0\", \"versionStartIncluding\": \"2.0.0-beta.1\"}], \"operator\": \"OR\"}], \"operator\": \"AND\"}], \"providerMetadata\": {\"orgId\": \"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\", \"shortName\": \"EEF\", \"dateUpdated\": \"2026-10-26T13:49:40.392Z\"}, \"x_proofOfConcept\": [{\"lang\": \"en\", \"value\": \"* Build a gzip stream whose inflated size is 1 GB from a reused 64 KB chunk of zero bytes (deflate with window bits 31, best compression). The stream is about 1 MB on the wire.\\n* Start a TCP listener on loopback that accepts one connection, reads the request, and answers HTTP/1.1 200 OK with Content-Encoding: gzip, a Content-Length matching the stream, Connection: close, and the stream as body.\\n* From a node running a vulnerable hackney, call hackney:request(get, Url, [], \u003c\u003c\u003e\u003e, [{auto_decompress, true}, with_body]) against that listener.\\n* Observe the returned body of 1,048,576,000 bytes and the VM memory growing by about 1.8 GB for a 1,019,197 byte response. A larger stream, or an endless body without auto_decompress, drives the node out of memory.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003col\u003e\\n\u003cli\u003eBuild a gzip stream whose inflated size is 1 GB from a reused 64 KB chunk of zero bytes (deflate with window bits 31, best compression). The stream is about 1 MB on the wire.\u003c/li\u003e\\n\u003cli\u003eStart a TCP listener on loopback that accepts one connection, reads the request, and answers \u003ccode\u003eHTTP/1.1 200 OK\u003c/code\u003e with \u003ccode\u003eContent-Encoding: gzip\u003c/code\u003e, a \u003ccode\u003eContent-Length\u003c/code\u003e matching the stream, \u003ccode\u003eConnection: close\u003c/code\u003e, and the stream as body.\u003c/li\u003e\\n\u003cli\u003eFrom a node running a vulnerable hackney, call \u003ccode\u003ehackney:request(get, Url, [], \u0026lt;\u0026lt;\u0026gt;\u0026gt;, [{auto_decompress, true}, with_body])\u003c/code\u003e against that listener.\u003c/li\u003e\\n\u003cli\u003eObserve the returned body of 1,048,576,000 bytes and the VM memory growing by about 1.8 GB for a 1,019,197 byte response. A larger stream, or an endless body without \u003ccode\u003eauto_decompress\u003c/code\u003e, drives the node out of memory.\u003c/li\u003e\\n\u003c/ol\u003e\", \"base64\": false}, {\"type\": \"text/markdown\", \"value\": \"1. Build a gzip stream whose inflated size is 1 GB from a reused 64 KB chunk of zero bytes (deflate with window bits 31, best compression). The stream is about 1 MB on the wire.\\n2. Start a TCP listener on loopback that accepts one connection, reads the request, and answers `HTTP/1.1 200 OK` with `Content-Encoding: gzip`, a `Content-Length` matching the stream, `Connection: close`, and the stream as body.\\n3. From a node running a vulnerable hackney, call `hackney:request(get, Url, [], \u003c\u003c\u003e\u003e, [{auto_decompress, true}, with_body])` against that listener.\\n4. Observe the returned body of 1,048,576,000 bytes and the VM memory growing by about 1.8 GB for a 1,019,197 byte response. A larger stream, or an endless body without `auto_decompress`, drives the node out of memory.\", \"base64\": false}]}], \"x_technicalAnalysis\": [{\"lang\": \"en\", \"value\": \"1. Unbounded accumulation. hackney:request/5 with a body, and hackney:body/1 after start_response/1, read the response in src/hackney_conn.erl through read_full_body/2, which appends each chunk to a binary accumulator until the body ends. The HTTP/2 and HTTP/3 synchronous paths accumulate stream data the same way. No option caps the size.\\n\\n2. One-step decompression. With {auto_decompress, true} hackney sends Accept-Encoding: gzip, deflate. Once the body is complete, maybe_decompress_body/2 dispatches on Content-Encoding to decompress_gzip/1 (zlib:gunzip/1) or decompress_deflate/1 (zlib:inflate/2). Both return the whole output at once, so the inflated size is bounded only by the compression ratio. The report measured a 1 MB gzip body inflating to 1 GB on hackney 4.8.4.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"\u003cp\u003e\u003cstrong\u003e1. Unbounded accumulation.\u003c/strong\u003e \u003ccode\u003ehackney:request/5\u003c/code\u003e with a body, and \u003ccode\u003ehackney:body/1\u003c/code\u003e after \u003ccode\u003estart_response/1\u003c/code\u003e, read the response in \u003ccode\u003esrc/hackney_conn.erl\u003c/code\u003e through \u003ccode\u003eread_full_body/2\u003c/code\u003e, which appends each chunk to a binary accumulator until the body ends. The HTTP/2 and HTTP/3 synchronous paths accumulate stream data the same way. No option caps the size.\u003c/p\u003e\\n\u003cp\u003e\u003cstrong\u003e2. One-step decompression.\u003c/strong\u003e With \u003ccode\u003e{auto_decompress, true}\u003c/code\u003e hackney sends \u003ccode\u003eAccept-Encoding: gzip, deflate\u003c/code\u003e. Once the body is complete, \u003ccode\u003emaybe_decompress_body/2\u003c/code\u003e dispatches on \u003ccode\u003eContent-Encoding\u003c/code\u003e to \u003ccode\u003edecompress_gzip/1\u003c/code\u003e (\u003ccode\u003ezlib:gunzip/1\u003c/code\u003e) or \u003ccode\u003edecompress_deflate/1\u003c/code\u003e (\u003ccode\u003ezlib:inflate/2\u003c/code\u003e). Both return the whole output at once, so the inflated size is bounded only by the compression ratio. The report measured a 1 MB gzip body inflating to 1 GB on hackney 4.8.4.\u003c/p\u003e\", \"base64\": false}, {\"type\": \"text/markdown\", \"value\": \"**1. Unbounded accumulation.** `hackney:request/5` with a body, and `hackney:body/1` after `start_response/1`, read the response in `src/hackney_conn.erl` through `read_full_body/2`, which appends each chunk to a binary accumulator until the body ends. The HTTP/2 and HTTP/3 synchronous paths accumulate stream data the same way. No option caps the size.\\n\\n**2. One-step decompression.** With `{auto_decompress, true}` hackney sends `Accept-Encoding: gzip, deflate`. Once the body is complete, `maybe_decompress_body/2` dispatches on `Content-Encoding` to `decompress_gzip/1` (`zlib:gunzip/1`) or `decompress_deflate/1` (`zlib:inflate/2`). Both return the whole output at once, so the inflated size is bounded only by the compression ratio. The report measured a 1 MB gzip body inflating to 1 GB on hackney 4.8.4.\", \"base64\": false}]}]}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-97200\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-10-26T15:35:50.487Z\", \"dateReserved\": \"2026-10-26T05:15:01.465Z\", \"assignerOrgId\": \"6b3ad84c-e1a6-4bf7-a703-f496b71e49db\", \"datePublished\": \"2026-10-26T13:49:40.392Z\", \"assignerShortName\": \"EEF\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}