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TI-2026-02259 Aliases CVE-2026-2646GHSA-24vq-qfc5-qrmj

Heap buffer overflow in session parsing with wolfSSL_d2i_SSL_SESSION() function

Priority LOW 22CWE-122Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
High
Attack requirements
Present
Impact type
—
Confidentiality · integrity · availability
Low · High · High
Fix status
No fix listed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA.

Summary

A heap-buffer-overflow vulnerability exists in wolfSSL's wolfSSL_d2i_SSL_SESSION() function. When deserializing session data with SESSION_CERTS enabled, certificate and session id lengths are read from an untrusted input without bounds validation, allowing an attacker to overflow fixed-size buffers and corrupt heap memory. A maliciously crafted session would need to be loaded from an external source to trigger this vulnerability. Internal sessions were not vulnerable.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00128 2nd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
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
wolfSSLwolfsslup to 5.8.4—No fix listedCNA
  • wolfssl VendorwolfSSL Affected up to 5.8.4 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*before 5.9.0VulnerablewolfSSL
  • cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:* Versions before 5.9.0 Vulnerable ·wolfSSL

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-2646
  2. 2026-10-03 Alias added: GHSA-24vq-qfc5-qrmj

References

Patch 2

  • TI-2024-00830 SEGV and out of bounds memory read from malicious packet CVSS 3.1CRITICAL 9.1
  • TI-2022-18557 In wolfSSL before 5.5.1, malicious clients can cause a buffer overflow during a TLS 1.3… CVSS 3.1HIGH 7.5
  • TI-2025-10943 Potential DoS Vulnerability through Multiple KeyShareEntry with Same Group in TLS 1.3 ClientHello CVSS 4.0MEDIUM 6.3
  • TI-2017-09737 wolfSSL Bleichenbacher/ROBOT CVSS 3.0HIGH 7.5
  • TI-2019-08902 wolfSSL 4.0.0 has a Buffer Overflow in DoPreSharedKeys in tls13.c when a current identity… CVSS 3.1CRITICAL 9.8
  • TI-2017-02021 Improper certificate validation in wolfSSL CVSS 3.1CRITICAL 9.8
See all 150 →

Sources

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