CVE-2026-5392 wolfSSL heap OOB read in PKCS7 SignedData streaming

Low 2.3 Published 9 Apr 2026 Updated 10 Apr 2026

A crafted PKCS7 message triggers a heap out-of-bounds read in wolfSSL, potentially causing crashes or leaking memory.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Local or same network only
Victim action needed: Not needed
Fix: Available

What is CVE-2026-5392?

CVE-2026-5392 is a low-severity memory corruption vulnerability in Wolfssl Wolfssl, published on 9 Apr 2026. It can only be exploited from the same machine or local network, with no action from the victim.

Official description

Heap out-of-bounds read in PKCS7 parsing. A crafted PKCS7 message can trigger an OOB read on the heap. The missing bounds check is in the indefinite-length end-of-content verification loop in PKCS7_VerifySignedData().

Weakness: CWE-125

Which versions are affected by CVE-2026-5392?

It affects 1 product.

Products include Wolfssl Wolfssl.

How do I fix CVE-2026-5392?

Apply the vendor's patch.

Upgrade to the fixed version. Memory-safe languages, compiler hardening and fuzzing prevent most new cases. More about Memory corruption.

Is CVE-2026-5392 being exploited?

There is no known exploitation of CVE-2026-5392 in the wild and no public exploit code.

All Wolfssl Wolfssl vulnerabilities

Sources

Also known as DEBIAN-CVE-2026-5392, GHSA-52wm-3mqv-vmmj, JLSEC-2026-720, UBUNTU-CVE-2026-5392.