CVE-2026-5504 (GCVE-0-2026-5504)

Vulnerability from cvelistv5 – Published: 2026-04-09 22:33 – Updated: 2026-04-09 22:33
VLAI?
Title
PKCS7 CBC Padding Oracle — Plaintext Recovery
Summary
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.
Severity ?
6.3 (Medium)
CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-354 - Improper validation of integrity check value
Assigner
References
Impacted products
Vendor Product Version
wolfSSL wolfSSL Affected: 0 , ≤ 5.9.0 (semver)
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Credits
Sunwoo Lee of Korea Institute of Energy Technology (KENTECH) for the report. Woohyun Choi of Korea Institute of Energy Technology (KENTECH) for the report. Seunghyun Yoon of Korea Institute of Energy Technology (KENTECH) for the report.
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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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Detection rules are retrieved from Rulezet.