CVE-2026-5507: Session Cache Restore — Arbitrary Free via Deserialized Pointer

Severity: medium (CVSS 4.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-09 · updated 2026-06-17
Weakness: CWE-502

Description

When restoring a session from cache, a pointer from the serialized session data is used in a free operation without validation. An attacker who can poison the session cache could trigger an arbitrary free. Exploitation requires the ability to inject a crafted session into the cache and for the application to call specific session restore APIs.

Affected products

wolfSSL: through 5.9.0

References

https://github.com/wolfSSL/wolfssl/pull/10088

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