CVE-2026-15442: wolfSSL heap-use-after-free in TLS shutdown

CVE-2026-15442 · Severity: info · Published 2026-09-27

wolfSSL is a cryptographic library used to secure network communications via TLS/DTLS. Under specific conditions during TLS connection shutdown—when an application reads partial data into a small buffer, initiates shutdown, and attempts to read again while the peer sends data—a heap-use-after-free vulnerability can occur, potentially leading to memory corruption or information disclosure.

Technologies: Wolfssl. Vendors: Wolfssl.

Quick answers

Is CVE-2026-15442 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-15442 being exploited in the wild.
How severe is CVE-2026-15442?
Informational severity, published 27 September 2026.
Which products and versions are affected?
wolfSSL wolfSSL.
Is there a fix for CVE-2026-15442?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2026-15442 attacked?
It is attacked over the network.
Am I affected by CVE-2026-15442?
Check whether you run Wolfssl. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

A heap-use-after-free occurs in wolfSSL's TLS shutdown sequence when specific conditional states are reached: a partial wolfSSL_read() with a small user buffer, followed by wolfSSL_shutdown() for bidirectional close, and another wolfSSL_read() attempt while the peer continues sending data. This requires application-level interaction and specific timing but affects all builds using (D)TLS by default. A fix has been merged upstream.

Affected products

  • wolfSSL wolfSSL

References

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