CVE-2026-70368

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".

Overview

State: PUBLISHED
Assigner (CNA): redhat
CVSS severity: MEDIUM
CVSS score: 6.5 / 10
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Effective score: 6.5 / 10 MEDIUM source: CNA overview
CWE(s): CWE-125
Reserved: 2026-08-04
Published: 2026-08-04 13:52 UTC
Last updated: 2026-08-04 14:21 UTC
Source: https://raw.githubusercontent.com/CVEProject/cvelistV5/main/cves/2026/70xxx/CVE-2026-70368.json

Affected products (5)

Vendor	Product	Versions	Platforms
Red Hat	Red Hat Enterprise Linux 10	—	—
Red Hat	Red Hat Enterprise Linux 6	—	—
Red Hat	Red Hat Enterprise Linux 7	—	—
Red Hat	Red Hat Enterprise Linux 8	—	—
Red Hat	Red Hat Enterprise Linux 9	—	—

Vendor references (2)

References embedded in the original CVE record by the assigning CNA.

https://access.redhat.com/security/cve/CVE-2026-70368 vdb-entryx_refsource_REDHAT
RHBZ#2462029 issue-trackingx_refsource_REDHAT

Web references (0)

DuckDuckGo results ranked by threat-intel / vendor advisory domains. Generated by the 🔎 Find references (web) button above — same flow as the Remediations search.

No web references attached yet.

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Raw JSON

The full cvelistV5 record. Download as CVE-2026-70368.json.

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