CVE-2026-109438

MEDIUM
MEDIUM Priority: 0.02 BB Relevance: 73/100
Published: 2026-10-14 Modified: 2026-10-27 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
AT: Present
VC: Low
VI: None
VA: None

Description

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.

Weakness Classification (1)

Bug Bounty Relevance

73 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

6.3 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

EPSS — Exploitation Probability

0.36%
Raw Score 0.003590
Percentile 29.6%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00359
2026-10-28
0.00359

Intelligence Sources

mitre ref →