CVE-2026-70368

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".

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://access.redhat.com/security/cve/CVE-2026-70368
https://bugzilla.redhat.com/show_bug.cgi?id=2462029

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-04 14:16

Updated : 2026-08-06 15:37

NVD link : CVE-2026-70368

Mitre link : CVE-2026-70368

CVE.ORG link : CVE-2026-70368

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

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