CVE-2026-5187: low-severity vulnerability in wolfSSL
Heap Out-of-Bounds Write in DecodeObjectId() in wolfSSL
Published · Updated
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8Vexday Risk Score
No sign of exploitation. No public exploitation artifact known so far.
ssvc Trackcvss 2.3epss 0.3%
Two potential heap out-of-bounds write locations existed in DecodeObjectId() in wolfcrypt/src/asn.c. First, a bounds check only validates one available slot before writing two OID arc values (out[0] and out[1]), enabling a 2-byte out-of-bounds write when outSz equals 1. Second, multiple callers pass sizeof(decOid) (64 bytes on 64-bit platforms) instead of the element count MAX_OID_SZ (32), causing the function to accept crafted OIDs with 33 or more arcs that write past the end of the allocated buffer.
CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
Affected products
wolfSSL · wolfSSLRelated CVEs — wolfSSL
In the same product, most dangerous first.
CVE-2017-13099HIGHwolfSSL Bleichenbacher/ROBOTEPSS 27.4%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-2023-6936MEDIUM Heap-buffer over-read with WOLFSSL_CALLBACKSEPSS 0.6%CVE-2026-5194CRITICALwolfSSL ECDSA Certificate VerificationEPSS 0.6%
References
https://github.com/wolfSSL/wolfssl