CVE-2026-5187 (GCVE-0-2026-5187)

Vulnerability from cvelistv5 – Published: 2026-04-09 19:45 – Updated: 2026-04-09 19:45
VLAI?
Title
Heap Out-of-Bounds Write in DecodeObjectId() in wolfSSL
Summary
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.
Severity ?
2.3 (Low)
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
CWE
Assigner
References
Impacted products
Vendor Product Version
wolfSSL wolfSSL Affected: 0 , ≤ 5.9.0 (semver)
Create a notification for this product.
Credits
ytsun, Independent Security Researcher
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