CVE-2026-2646 (GCVE-0-2026-2646)

Vulnerability from cvelistv5 – Published: 2026-03-19 17:25 – Updated: 2026-03-19 17:44
VLAI
Title
Heap buffer overflow in session parsing with wolfSSL_d2i_SSL_SESSION() function
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.
Severity
5 (Medium)
CVSS:4.0/AV:L/AC:H/AT:P/PR:L/UI:N/VC:L/VI:H/VA:H/SC:N/SI:N/SA:N/E:P
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-19 17:43 UTC
CWE
  • CWE-122 - Heap-based Buffer Overflow
Assigner
wolfSSL CNA under the icscert root
CNA scorecard B 80/100 over 51 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
wolfssl wolfssl Affected: 0 , ≤ 5.8.4 (semver)
guessed Create a notification for this product.
Credits
Jonathan Bar Or (@yo_yo_yo_jbo) Haruto Kimura (Stella)
Show details on NVD website
To clipboard 

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