CVE-2026-109438 (GCVE-0-2026-109438)
Vulnerability from cvelistv5 – Published: 2026-10-14 15:53 – Updated: 2026-10-15 19:02 X_Open Source
VLAI
EPSS
VEX
Title
3proxy 0.9.7 - 1.0.1 Uninitialized Stack Memory Disclosure via SOCKS4
Summary
3proxy from 0.9.7 through 1.0.1, fixed in commit 206c923, contains an uninitialized stack memory disclosure vulnerability that allows unauthenticated attackers to leak stack bytes via the SOCKS4 reply path when the external-NAT option (-Ne) is configured. Attackers can send a client probe that fails the SOCKS version check to trigger a reply containing uninitialized bytes from the sin structure, exposing high bytes of a userspace pointer that weakens ASLR protections.
Severity
5.3 (Medium)
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-15 19:01 UTC
CWE
- CWE-908 - Use of Uninitialized Resource
Assigner
References
2 references
| URL | Tags |
|---|---|
| https://github.com/3proxy/3proxy/commit/206c923d6… | patchissue-tracking |
| https://www.vulncheck.com/advisories/3proxy-unini… | third-party-advisory |
Impacted products
Date Public
2026-10-12 00:00
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