CVE-2026-76956 (GCVE-0-2026-76956)
Vulnerability from cvelistv5
Published
2026-08-20 04:22
Modified
2026-08-20 17:42
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-394 - Unexpected Status Code or Return Value
Summary
In libexpat 2.8.2 and 2.8.3 before 2.8.4, misinterpretation of getentropy's return code leads to insufficient entropy, which results in being vulnerable to hash flooding attacks, causing a denial of service via crafted XML content.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| libexpat project | libexpat |
Version: 2.8.2 ≤ |
{
"containers": {
"adp": [
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2026-76956",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "yes"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2026-08-20T15:05:31.739781Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2026-08-20T15:26:28.115Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "libexpat",
"vendor": "libexpat project",
"versions": [
{
"lessThan": "2.8.4",
"status": "affected",
"version": "2.8.2",
"versionType": "semver"
}
]
}
],
"cpeApplicability": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*",
"versionEndExcluding": "2.8.4",
"versionStartIncluding": "2.8.2",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In libexpat 2.8.2 and 2.8.3 before 2.8.4, misinterpretation of getentropy\u0027s return code leads to insufficient entropy, which results in being vulnerable to hash flooding attacks, causing a denial of service via crafted XML content."
}
],
"metrics": [
{
"cvssV3_1": {
"attackComplexity": "HIGH",
"attackVector": "NETWORK",
"availabilityImpact": "HIGH",
"baseScore": 5.9,
"baseSeverity": "MEDIUM",
"confidentialityImpact": "NONE",
"integrityImpact": "NONE",
"privilegesRequired": "NONE",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H",
"version": "3.1"
},
"format": "CVSS",
"scenarios": [
{
"lang": "en",
"value": "GENERAL"
}
]
}
],
"problemTypes": [
{
"descriptions": [
{
"cweId": "CWE-394",
"description": "CWE-394 Unexpected Status Code or Return Value",
"lang": "en",
"type": "CWE"
}
]
}
],
"providerMetadata": {
"dateUpdated": "2026-08-20T17:42:38.849Z",
"orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
"shortName": "mitre"
},
"references": [
{
"url": "https://github.com/libexpat/libexpat/pull/1326"
},
{
"url": "https://github.com/libexpat/libexpat/pull/1329"
}
],
"x_generator": {
"engine": "CVE-Request-form 0.0.1"
}
}
},
"cveMetadata": {
"assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca",
"assignerShortName": "mitre",
"cveId": "CVE-2026-76956",
"datePublished": "2026-08-20T04:22:51.381Z",
"dateReserved": "2026-08-20T04:22:50.503Z",
"dateUpdated": "2026-08-20T17:42:38.849Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
"dataVersion": "5.2",
"vulnerability-lookup:meta": {
"vulnrichment": {
"containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-76956\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-08-20T15:05:31.739781Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-08-20T15:22:07.648Z\"}}], \"cna\": {\"metrics\": [{\"format\": \"CVSS\", \"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 5.9, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H\", \"integrityImpact\": \"NONE\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"HIGH\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"NONE\"}, \"scenarios\": [{\"lang\": \"en\", \"value\": \"GENERAL\"}]}], \"affected\": [{\"vendor\": \"libexpat project\", \"product\": \"libexpat\", \"versions\": [{\"status\": \"affected\", \"version\": \"2.8.2\", \"lessThan\": \"2.8.4\", \"versionType\": \"semver\"}], \"defaultStatus\": \"unaffected\"}], \"references\": [{\"url\": \"https://github.com/libexpat/libexpat/pull/1326\"}, {\"url\": \"https://github.com/libexpat/libexpat/pull/1329\"}], \"x_generator\": {\"engine\": \"CVE-Request-form 0.0.1\"}, \"descriptions\": [{\"lang\": \"en\", \"value\": \"In libexpat 2.8.2 and 2.8.3 before 2.8.4, misinterpretation of getentropy\u0027s return code leads to insufficient entropy, which results in being vulnerable to hash flooding attacks, causing a denial of service via crafted XML content.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-394\", \"description\": \"CWE-394 Unexpected Status Code or Return Value\"}]}], \"cpeApplicability\": [{\"nodes\": [{\"negate\": false, \"cpeMatch\": [{\"criteria\": \"cpe:2.3:a:libexpat_project:libexpat:*:*:*:*:*:*:*:*\", \"vulnerable\": true, \"versionEndExcluding\": \"2.8.4\", \"versionStartIncluding\": \"2.8.2\"}], \"operator\": \"OR\"}]}], \"providerMetadata\": {\"orgId\": \"8254265b-2729-46b6-b9e3-3dfca2d5bfca\", \"shortName\": \"mitre\", \"dateUpdated\": \"2026-08-20T17:42:38.849Z\"}}}",
"cveMetadata": "{\"cveId\": \"CVE-2026-76956\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-08-20T17:42:38.849Z\", \"dateReserved\": \"2026-08-20T04:22:50.503Z\", \"assignerOrgId\": \"8254265b-2729-46b6-b9e3-3dfca2d5bfca\", \"datePublished\": \"2026-08-20T04:22:51.381Z\", \"assignerShortName\": \"mitre\"}",
"dataType": "CVE_RECORD",
"dataVersion": "5.2"
}
}
}
Loading…
Loading…
Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
Loading…
Loading…