CVE-2026-70368
Severity CVSS v4.0:
Pending analysis
Type:
CWE-125
Out-of-bounds Read
Publication date:
04/08/2026
Last modified:
04/08/2026
Description
A stack-based out-of-bounds read vulnerability exists in the "s_vlog" function of stunnel, when handling oversized log messages via "vsnprintf". A remote attacker with network access to a stunnel service can send protocol inputs that trigger a log message longer than 1024 bytes, leading to an out-of-bounds stack read and a potential crash. In certain corner cases, the same vulnerability could be used to replace a series of trailing "\n" characters with "\0".
Impact
Base Score 3.x
6.50
Severity 3.x
MEDIUM