CVE-2026-109438

EUVD-2026-101290

14.10.2026, 16:17

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.

Provider	Type	Base Score	Atk. Vector	Atk. Complexity	Priv. Required	Vector
VulnCheck	CNA	5.3 MEDIUM	NETWORK	LOW	NONE	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N

Base Score

CVSS 3.x

EPSS Score

Percentile: Unknown

Early Detection

Affected products identified ahead of NVD analysis through intelligence sources.

Vendor	Product	Version	Source
3proxy	3proxy	0.9.7 ≤ 𝑥 ≤ 1.0.1	CNA

Common Weakness Enumeration

CWE-908 - Use of Uninitialized Resource
The software uses or accesses a resource that has not been initialized.

References

https://github.com/3proxy/3proxy/commit/206c923d6cd433bd2e7196375442650c328b8bfa

https://www.vulncheck.com/advisories/3proxy-uninitialized-stack-memory-disclosure-via-socks4