CVE-2013-4176

Information disclosure via shared-memory slot race

Published Jan 23, 2020 · Updated Aug 6, 2024

Information disclosure in MySecureShell 1.31 allows local users to access another user's directory during concurrent SFTP sessions. SftpWho.c allocates records from a 128-slot shared-memory table without synchronizing the check and reservation, allowing two processes to claim the same slot. Exploitation requires an authenticated local account and a scheduling race; process permissions remain unchanged, but another user's accessible files can be read.

CVSS severity5.5
Medium
EPSS probability0.43%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Information disclosure in MySecureShell 1.31 allows local users to access another user's directory during concurrent SFTP sessions. SftpWho.c allocates records from a 128-slot shared-memory table without synchronizing the check and reservation, allowing two processes to claim the same slot. Exploitation requires an authenticated local account and a scheduling race; process permissions remain unchanged, but another user's accessible files can be read.

The record

CVE
CVE-2013-4176
Published
Jan 23, 2020
Updated
Aug 6, 2024
Vendor
MySecureShell
Product
MySecureShell
Classifications
CWE-200, T1005
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 23, 2020CVE publishedPublication date reported by the CVE source.
  2. Aug 6, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=1.31

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

MySecureShell · MySecureShellversion=1.31

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
2.1NIST NVDAV:L/AC:L/Au:N/C:P/I:N/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-200Exposure of Sensitive Information to an Unauthorized Actor
T1005Data from Local System

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo