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CVE-2026-35189

medium

Issue summary: A certificate with many nameRelativeToCRLIssuer CRL distribution points causes disproportionate heap growth when OpenSSL caches X.509 extensions.

Vendor / product: Openssl — openssl

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.

CVSS
5.3
5.3 (CVSS v3.1)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Severity source: NVD CVSS v3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
Timeline (UTC)
Published: 2026-09-29 16:17
Modified: 2026-10-08 01:01
NVD status: Analyzed
Last synced 2 days ago
Verified against the source API 2026-10-27 06:56 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).

Affected products

openssl / openssl ≥1.0.2 <1.0.2zs, ≥1.1.1 <1.1.1zj, ≥3.0.0 <3.0.23, ≥3.4.0 <3.4.8, ≥3.5.0 <3.5.9, ≥3.6.0 <3.6.5

Weakness classification (CWE)

Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.

Mitigation & advisories

Vendor advisory: https://openssl-library.org/news/secadv/20260929.txt
Patch / mitigation: https://github.com/openssl/openssl/commit/2b93c73b2c70ddc4c61c5e4bfaaa6bd71379eb84
Patch / mitigation: https://github.com/openssl/openssl/commit/3842516cc15e8b2cf55747011045e77547e71d89
Patch / mitigation: https://github.com/openssl/openssl/commit/8e0efc7549b7ff8246d40e585e3fd604f728473f
Patch / mitigation: https://github.com/openssl/openssl/commit/c72ae182cac17a82e4246c6ecd4e9c4ec3586ec9

References

Data sources

NVD CVE API 2.0 — fetched 2026-10-27 06:56 UTC · record ↗

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