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.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/10102	Issue Tracking

Configurations

Configuration 1 (hide)

cpe:2.3:a:wolfssl:wolfssl:*:*:*:*:*:*:*:*

History

27 Apr 2026, 18:15

Type	Values Removed	Values Added
References	~~() https://github.com/wolfSSL/wolfssl/pull/10102 -~~	() https://github.com/wolfSSL/wolfssl/pull/10102 - Issue Tracking
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::
First Time		Wolfssl Wolfssl wolfssl
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.9

10 Apr 2026, 04:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-10 04:17

Updated : 2026-04-27 18:15

NVD link : CVE-2026-5500

Mitre link : CVE-2026-5500

CVE.ORG link : CVE-2026-5500

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-20

Improper Input Validation

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