CVE-2026-35189 (GCVE-0-2026-35189)

Vulnerability from cvelistv5 – Published: 2026-09-29 15:32 – Updated: 2026-09-29 15:32
VLAI
Title
Excessive Memory Allocation in Relative CRLDP Processing
Summary
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
No CVSS data available.
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
References
Impacted products
Vendor Product Version CPE status
OpenSSL OpenSSL Affected: 4.0.0 , < 4.0.3 (semver)
Affected: 3.6.0 , < 3.6.5 (semver)
Affected: 3.5.0 , < 3.5.9 (semver)
Affected: 3.4.0 , < 3.4.8 (semver)
Affected: 3.0.0 , < 3.0.23 (semver)
Affected: 1.1.1 , < 1.1.1zj (custom)
Affected: 1.0.2 , < 1.0.2zs (custom)
guessed Create a notification for this product.
Date Public
2026-09-29 14:21
Credits
Fuzz0x (ZKSC Institute of Security Research) Viktor Dukhovni
Show details on NVD website
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    "dateReserved": "2026-04-01T17:36:26.323Z",
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      "cve": "CVE-2026-35189",
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      "product_status:known_affected": "88",
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      "title": "openssl: openssl: Denial of Service via excessive memory allocation in CRL distribution point processing",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-35189.json",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.