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TI-2026-24345 Aliases CVE-2026-31789GHSA-j79m-9jxq-788r

Heap Buffer Overflow in Hexadecimal Conversion

Priority MEDIUM 42CWE-787Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
Partial Red Hat: 1 fixed, 8 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-787 and the CVSS impact.

Summary

Issue summary: Converting an excessively large OCTET STRING value to a hexadecimal string leads to a heap buffer overflow on 32 bit platforms. Impact summary: A heap buffer overflow may lead to a crash or possibly an attacker controlled code execution or other undefined behavior. If an attacker can supply a crafted X.509 certificate with an excessively large OCTET STRING value in extensions such as the Subject Key Identifier (SKID) or Authority Key Identifier (AKID) which are being converted to hex, the size of the buffer needed for the result is calculated as multiplication of the input length by 3. On 32 bit platforms, this multiplication may overflow resulting in the allocation of a smaller buffer and a heap buffer overflow. Applications and services that print or log contents of untrusted X.509 certificates are vulnerable to this issue. As the certificates would have to have sizes of over 1 Gigabyte, printing or logging such certificates is a fairly unlikely operation and only 32 bit platforms are affected, this issue was assigned Low severity. The FIPS modules in 3.6, 3.5, 3.4, 3.3 and 3.0 are not 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 0.00253 16th percentileScored 2026-11-07
Fix Partial OpenSSL (OpenSSL): 3.6.2, 3.5.6, 3.4.5 +2Red Hat: 1 advisoryRed Hat: 1 fixed, 8 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

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

Affected products

VendorProductAffected versionsFixed inStatusSource
OpenSSLOpenSSL3.6.0 to before 3.6.2; 3.5.0 to before 3.5.6; 3.4.0 to before 3.4.5; 3.3.0 to before 3.3.7; 3.0.0 to before 3.0.203.6.2, 3.5.6, 3.4.5, 3.3.7, 3.0.20Patch availableCNA
  • OpenSSL VendorOpenSSL Affected 3.6.0 to before 3.6.2; 3.5.0 to before 3.5.6; 3.4.0 to before 3.4.5; 3.3.0 to before 3.3.7; 3.0.0 to before 3.0.20 Fixed in 3.6.2, 3.5.6, 3.4.5, 3.3.7, 3.0.20 Patch available CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:*3.0.0 to before 3.0.20; 3.3.0 to before 3.3.7; 3.4.0 to before 3.4.5; 3.5.0 to before 3.5.6; 3.6.0 to before 3.6.2VulnerableOpenSSL
  • cpe:2.3:a:openssl:openssl:*:*:*:*:*:*:*:* Versions 3.0.0 to before 3.0.20; 3.3.0 to before 3.3.7; 3.4.0 to before 3.4.5; 3.5.0 to before 3.5.6; 3.6.0 to before 3.6.2 Vulnerable ·OpenSSL

Remediation

  • Fix · CNA OpenSSL (OpenSSL) Fixed in 3.6.2, 3.5.6, 3.4.5, 3.3.7, 3.0.20

Red Hat 1 advisory

  • RHSA-2026:7261 Released 2026-04-09 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images openssl-3.5.6-0.1.hum1@aarch64, openssl-3.5.6-0.1.hum1@src, openssl-3.5.6-0.1.hum1@x86_64 +10

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/20260407.txt

    7 records Highest priority Priority MEDIUM 6 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-22661 Out-of-bounds Read in AES-CFB-128 on X86-64 with AVX-512 SupportPriority MEDIUM 46
    • TI-2026-24346 Incorrect Failure Handling in RSA KEM RSASVE EncapsulationPriority MEDIUM 41
    • TI-2026-22663 NULL Pointer Dereference When Processing a Delta CRLPriority MEDIUM 41
    Show all 7 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 OpenShift AI (RHOAI)Affected—
Red Hat OpenShift Container Platform 4AffectedNo fix yet: Fix deferred
Red Hat Hardened ImagesFixed RHSA-2026:7261
Not affected: 1 product
  • Red Hat OpenShift AI (RHOAI)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-31789
  2. 2026-10-03 Alias added: GHSA-j79m-9jxq-788r
  3. 2026-11-06 Affected versions changed · Red Hat

References

Patch 5

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