CVE-2026-35189
Full vulnerability record from the local CVENow database.
Description
Issue summary: A certificate with many nameRelativeToCRLIssuer CRL distribution points causes disproportionate heap growth when OpenSSL caches X.509 extensions. Impact summary: Receiving a crafted certificate from a malicious peer can lead to significant memory pressure and possible Denial of Service in clients or in servers that solicit client certificates. CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: A certificate or a set of certificates that fits under the limit for size of certificates accepted from the peer (~100 KiB) can result in allocation of several hundred MiB of resident memory on the receiving side during a normal TLS handshake. This may be enough to crash the client or server, if multiple concurrent connections lead to similarly large memory allocations. The fix postpones processing of the CRL distribution points extensions in certificates to the time when the processed value is required for CRL processing. This avoids keeping large memory allocations for a long time when such certificates are received. FIPS impact: no The affected code is outside the FIPS module boundary.
Severity
MEDIUM
CVSS score
5.3
(v3.1)
Vulnerability status
Modified
Source identifier
Published
2026-09-29 16:17:07.330000
Last modified
2026-11-10 13:19:05.717000
View original CVE JSON
{
"id": "CVE-2026-35189",
"sourceIdentifier": "[email protected]",
"published": "2026-09-29T16:17:07.330",
"lastModified": "2026-11-10T13:19:05.717",
"vulnStatus": "Modified",
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"value": "Issue summary: A certificate with many nameRelativeToCRLIssuer CRL\ndistribution points causes disproportionate heap growth when OpenSSL caches\nX.509 extensions.\n\nImpact summary: Receiving a crafted certificate from a malicious peer can lead\nto significant memory pressure and possible Denial of Service in clients or\nin servers that solicit client certificates.\n\nCWE: CWE-770: Allocation of Resources Without Limits or Throttling\n\nDescription: A certificate or a set of certificates that fits under the limit for\nsize of certificates accepted from the peer (~100 KiB) can result in allocation\nof several hundred MiB of resident memory on the receiving side\nduring a normal TLS handshake. This may be enough to crash the client or\nserver, if multiple concurrent connections lead to similarly large memory\nallocations.\n\nThe fix postpones processing of the CRL distribution points extensions in\ncertificates to the time when the processed value is required for CRL processing.\nThis avoids keeping large memory allocations for a long time when such\ncertificates are received.\n\nFIPS impact: no\nThe affected code is outside the FIPS module boundary."
}
],
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{
"source": "[email protected]",
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"baseScore": 5.3,
"baseSeverity": "MEDIUM",
"attackVector": "NETWORK",
"attackComplexity": "LOW",
"privilegesRequired": "NONE",
"userInteraction": "NONE",
"scope": "UNCHANGED",
"confidentialityImpact": "NONE",
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"id": "CVE-2026-35189",
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