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.

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements Present

User Interaction None

Vulnerable System Confidentiality Impact Low

Vulnerable System Integrity Impact None

Vulnerable System Availability Impact None

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact Low

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

No EPSS score available.

Key SSVC decision points have not yet been added.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions
3proxy 3proxy unaffected
Version Status Constraints
0.9.7 affected ≤ 1.0.1
206c923d6cd433bd2e7196375442650c328b8bfa unaffected —

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Project Subscriptions

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Advisories

No advisories yet.

Fixes

Solution

No solution given by the vendor.

Workaround

No workaround given by the vendor.

References
Link Providers
https://github.com/3proxy/3proxy/commit/206c923d6cd433bd2e7196375442650c328b8bfa cve-icon cve-icon
https://www.vulncheck.com/advisories/3proxy-uninitialized-stack-memory-disclosure-via-socks4 cve-icon cve-icon
History

Wed, 14 Oct 2026 16:00:00 +0000

Type Values Removed Values Added
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.
Title 3proxy 0.9.7 - 1.0.1 Uninitialized Stack Memory Disclosure via SOCKS4
Weaknesses CWE-908
References
Metrics cvssV3_1

{'score': 5.3, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N'}

cvssV4_0

{'score': 6.3, 'vector': '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'}

Projects

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cve-icon MITRE

Status: PUBLISHED

Assigner: VulnCheck

Published:

Updated: 2026-10-14T15:53:36.065Z

Reserved: 2026-10-12T15:52:36.682Z

Link: CVE-2026-109438

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-14T16:17:36.783

Modified: 2026-10-14T16:17:36.783

Link: CVE-2026-109438

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

Weaknesses