CVE-2026-70368 (GCVE-0-2026-70368)

Vulnerability from cvelistv5 – Published: 2026-08-04 13:52 – Updated: 2026-08-06 07:33
VLAI
Title
Stunnel: stack-based out-of-bounds read/write in stunnel s_vlog via oversized log message
Summary
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".
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-04 14:21 UTC
CWE
Assigner
redhat CNA under the redhat root
CNA scorecard B 82/100 over 1039 records in the last 180 days details
References
URL Tags
https://access.redhat.com/security/cve/CVE-2026-70368 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2462029 issue-trackingx_refsource_REDHAT
Impacted products
Date Public
2026-08-04 10:30
Credits
This issue was discovered by Found by AISLE in partnership with Red Hat.
Show details on NVD website
To clipboard 

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