CVE-2026-5504

A padding oracle exists in wolfSSL's PKCS7 CBC decryption that could allow an attacker to recover plaintext through repeated decryption queries with modified ciphertext. In previous versions of wolfSSL the interior padding bytes are not validated.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/wolfSSL/wolfssl/pull/10088	Issue Tracking Patch

Configurations

Configuration 1 (hide)

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

History

29 Apr 2026, 14:06

Type	Values Removed	Values Added
First Time		Wolfssl Wolfssl wolfssl
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 5.3
References	~~() https://github.com/wolfSSL/wolfssl/pull/10088 -~~	() https://github.com/wolfSSL/wolfssl/pull/10088 - Issue Tracking, Patch
CPE		cpe:2.3:a:wolfssl:wolfssl::::::::

09 Apr 2026, 23:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-04-09 23:17

Updated : 2026-04-29 14:06

NVD link : CVE-2026-5504

Mitre link : CVE-2026-5504

CVE.ORG link : CVE-2026-5504

JSON object : View

Products Affected

wolfssl

wolfssl

CWE

CWE-354

Improper Validation of Integrity Check Value

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