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TI-2026-30988 Aliases CVE-2026-42765GHSA-vm8w-j6fw-jc7r

NULL Dereference in Certificate Verification with OCSP Checking

Priority LOW 39CWE-476Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 1 fixed, 10 without a fix

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA and Red Hat. Impact type from CWE-476.

Summary

Issue summary: When a partial-chain certificate verification is enabled together with OCSP response checking for the whole chain, a NULL dereference will happen if the verified chain does not have a self-signed trusted anchor, crashing the process. Impact summary: A NULL pointer dereference can trigger a crash which leads to a Denial of Service for an application. When performing OCSP response checking for certificates in the verification chain, the code always tries to access the next certificate as the issuer. There is a check for a self-signed certificate. However with the partial chain verification enabled when the chain does not have a self-signed trusted anchor, the issuer will be NULL for the last certificate in the chain. A NULL pointer dereference then happens. This issue affects only applications which enable both OCSP verification of the certificate chain (X509_V_FLAG_OCSP_RESP_CHECK_ALL) and partial chain verification (X509_V_FLAG_PARTIAL_CHAIN) in the certificate verification. Both flags are disabled by default. For that reason, we have assigned Low severity to the issue. No FIPS modules are affected by this issue as the affected code is outside the OpenSSL FIPS module boundary.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00508 43rd percentileScored 2026-11-07
Fix Partial OpenSSL (OpenSSL): 4.0.1, 3.6.3Red Hat: 8 advisoriesRed Hat: 1 fixed, 10 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
OpenSSLOpenSSL4.0.0 to before 4.0.1; 3.6.0 to before 3.6.34.0.1, 3.6.3Patch availableCNA
  • OpenSSL VendorOpenSSL Affected 4.0.0 to before 4.0.1; 3.6.0 to before 3.6.3 Fixed in 4.0.1, 3.6.3 Patch available CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*3.6.0 to before 3.6.3VulnerableOpenSSL
cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:*4.0.0VulnerableOpenSSL
  • cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* Versions 3.6.0 to before 3.6.3 Vulnerable ·OpenSSL
  • cpe:2.3:a:openssl:openssl:4.0.0:-:*:*:*:*:*:* Versions 4.0.0 Vulnerable ·OpenSSL

Remediation

  • Fix · CNA OpenSSL (OpenSSL) Fixed in 4.0.1, 3.6.3

Red Hat 8 advisories

  • RHSA-2026:67551 Released 2026-09-15 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images bootupd-0.3.2-1.hum1@aarch64, bootupd-0.3.2-1.hum1@x86_64, rust-bootupd-0.3.2-1.hum1@src
  • RHSA-2026:62790 Released 2026-09-02 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images ruby3.4-3.4.10-31.7.hum1@aarch64, ruby3.4-3.4.10-31.7.hum1@src, ruby3.4-3.4.10-31.7.hum1@x86_64 +10
  • RHSA-2026:62563 Released 2026-09-02 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images ruby4.0-4.0.6-37.3.hum1@aarch64, ruby4.0-4.0.6-37.3.hum1@src, ruby4.0-4.0.6-37.3.hum1@x86_64 +46
Show 5 more Red Hat advisories
  • RHSA-2026:62562 Released 2026-09-02 · Red Hat rating Important
    Red Hat Hardened Images RPMs Security Update
    • Red Hat Hardened Images ruby3.3-3.3.10-23.6.hum1@aarch64, ruby3.3-3.3.10-23.6.hum1@src, ruby3.3-3.3.10-23.6.hum1@x86_64 +46
  • RHSA-2026:59641 Released 2026-08-25 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images openssl-1:3.5.8-0.1.hum1@aarch64, openssl-1:3.5.8-0.1.hum1@src, openssl-1:3.5.8-0.1.hum1@x86_64 +12
  • RHSA-2026:59635 Released 2026-08-25 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images openssl3-1:3.5.8-0.1.hum1@src, openssl3-devel-1:3.5.8-0.1.hum1@aarch64, openssl3-devel-1:3.5.8-0.1.hum1@x86_64 +4
  • RHSA-2026:55543 Released 2026-08-17 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images python-cryptography-50.0.0-1.hum1@src, python3-cryptography-50.0.0-1.hum1@aarch64, python3-cryptography-50.0.0-1.hum1@x86_64
  • RHSA-2026:42825 Released 2026-07-21 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images chunkah-0.6.0-3.hum1@aarch64, chunkah-0.6.0-3.hum1@src, chunkah-0.6.0-3.hum1@x86_64

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    OpenSSL — openssl-library.org/news/secadv/20260609.txt

    18 records Highest priority Priority MEDIUM 6 MEDIUM, 12 LOW

    Other records, highest priority first

    • TI-2026-33226 Heap Use-After-Free in the PKCS7_verify() FunctionPriority MEDIUM 47
    • TI-2026-26479 CMS AuthEnvelopedData Processing May Accept Forged MessagesPriority MEDIUM 47
    • TI-2026-30987 NULL Pointer Dereference in QUIC Server Initial Packet HandlingPriority MEDIUM 41
    Show all 18 records → Advisory →

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 6AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 7AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux 9AffectedNo fix yet: Fix deferred
Red Hat JBoss Core ServicesAffectedNo fix yet: Fix deferred
Red Hat JBoss Web Server 6AffectedNo fix yet: Fix deferred
Red Hat JBoss Web Server 7AffectedNo fix yet: Fix deferred
Red Hat OpenShift AI (RHOAI)Affected—
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat Hardened ImagesFixed RHSA-2026:42825, RHSA-2026:55543, RHSA-2026:59635, RHSA-2026:59641, RHSA-2026:62562, RHSA-2026:62563, RHSA-2026:62790, RHSA-2026:67551
Not affected: 2 products
  • Red Hat Hardened Images
  • Red Hat OpenShift AI (RHOAI)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-42765
  2. 2026-10-03 Alias added: GHSA-vm8w-j6fw-jc7r
  3. 2026-11-06 Affected versions changed · Red Hat

References

Patch 2

Advisory 1

  • TI-2022-01915 The c_rehash script allows command injection CVSS 3.1CRITICAL 9.8
  • TI-2021-02645 SM2 Decryption Buffer Overflow CVSS 3.1CRITICAL 9.8
  • TI-2009-03392 The TLS protocol, and the SSL protocol 3.0 and possibly earlier, as used in Microsoft… CVSS 3.1CRITICAL 9.8
  • TI-2022-01176 The c_rehash script allows command injection CVSS 3.1CRITICAL 9.8
  • TI-2014-00154 The (1) TLS and (2) DTLS implementations in OpenSSL 1.0.1 before 1.0.1g do not properly… KEVCVSS 3.1HIGH 7.5
  • TI-2025-14107 Stack buffer overflow in CMS (Auth)EnvelopedData parsing CVSS 3.1HIGH 8.8
See all 312 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences