Improper input validation in Wolfssl

CVE-2026-5500

wolfSSL's wc_PKCS7_DecodeAuthEnvelopedData() does not properly sanitize the AES-GCM authentication tag length received and has no lower bounds check. A man-in-the-middle can therefore truncate the mac field from 16 bytes to 1 byte, reducing the tag check from 2⁻¹²⁸ to 2⁻⁸.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.004 (28.2th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 5.9 (Medium). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-5500?
CVE-2026-5500 is a medium-severity vulnerability in Wolfssl, classified under Improper Input Validation. CVSS score: 5.9/10. Published 2026-04-10.
How severe is CVE-2026-5500?
Medium severity. CVSS v3 base score is 5.9 out of 10.