CVE-2026-5504: medium-severity vulnerability in wolfSSL
PKCS7 CBC Padding Oracle — Plaintext Recovery
Published · Updated
13Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 6.3epss 0.1%
exploitation probability
0.1%top 96% of all CVEs
observed exploitation
nono source reports it
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:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Affected products
wolfSSL · wolfSSLRelated CVEs — wolfSSL
In the same product, most dangerous first.
CVE-2017-13099HIGHwolfSSL Bleichenbacher/ROBOTEPSS 24.9%CVE-2017-2800HIGHCVE-2017-2800EPSS 8.5%CVE-2024-0901HIGHSEGV and out of bounds memory read from malicious packetEPSS 0.7%CVE-2023-3724CRITICALTLS 1.3 client issue handling malicious server when not including a KSE and PSK extensionEPSS 0.7%CVE-2026-3548HIGHBuffer overflow in CRL number parsing in wolfSSLEPSS 0.6%CVE-2023-6936MEDIUM Heap-buffer over-read with WOLFSSL_CALLBACKSEPSS 0.6%