CVE-2026-5187CWE-122CWE-787

Heap Out-of-Bounds Write in DecodeObjectId() in wolfSSL

Low · published April 9, 2026

CVSS v4.0
2.3
EPSS
0%
Percentile
40.8
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v4.0
2.3 · LOW
Vector
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
EPSS
0.00484 · 40.8th percentile
Weaknesses
CWE-122 · Heap-based Buffer Overflow; CWE-787 · Out-of-bounds Write
Published
2026-04-09T19:45Z
EPSS history
Timeline
  • 09 APR 19:45Z
    Heap Out-of-Bounds Write in DecodeObjectId() in wolfSSL
    cvelistv5