CVE-2026-123613 (GCVE-0-2026-123613)

Vulnerability from cvelistv5 – Published: 2026-11-08 01:38 – Updated: 2026-11-08 01:38
VLAI
Title
Rustls 0.23.13 before 0.23.45 TLS 1.3 Handshake Encryption Level Bypass
Summary
Rustls from 0.23.13 before 0.23.45 accepts TLS 1.3 handshake messages at the wrong encryption level when they follow a key-changing message in the same record, because Deframer::aligned does not enforce RFC 8446 record-boundary alignment. A peer or on-path attacker can pack a plaintext EncryptedExtensions with the ServerHello, which rustls accepts unencrypted.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
CWE
  • CWE-20 - Improper Input Validation
Assigner
VulnCheck CNA
References
Impacted products
Vendor Product Version
rustls rustls Affected: 0.23.13 , < 0.23.45 (semver)
Unaffected: 0.23.45 (semver)
    cpe:2.3:a:rustls_project:rustls:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-09-14 00:00
Credits
randombit
Show details on NVD website
To clipboard 

{
  "containers": {
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          "defaultStatus": "unaffected",
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              "version": "0.23.45",
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        }
      ],
      "metrics": [
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      "problemTypes": [
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              "description": "Improper Input Validation",
              "lang": "en",
              "type": "CWE"
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      "providerMetadata": {
        "dateUpdated": "2026-11-08T01:38:37.574Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
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      "references": [
        {
          "name": "GitHub Security Advisory (GHSA-2mjx-qc3c-rqvc)",
          "tags": [
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          "url": "https://github.com/rustls/rustls/security/advisories/GHSA-2mjx-qc3c-rqvc"
        },
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        },
        {
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          "tags": [
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        }
      ],
      "title": "Rustls 0.23.13 before 0.23.45 TLS 1.3 Handshake Encryption Level Bypass",
      "x_generator": {
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  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-123613",
    "datePublished": "2026-11-08T01:38:37.574Z",
    "dateReserved": "2026-11-06T01:02:39.794Z",
    "dateUpdated": "2026-11-08T01:38:37.574Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}



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