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No exploitation reportedFix available

CVE-2025-5449

Libssh: integer overflow in libssh sftp server packet length validation leading to denial of service

No exploitation reported by the sources we read.

  • Published2025-07-25
  • WeaknessCWE-190

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

A flaw was found in the SFTP server message decoding logic of libssh. The issue occurs due to an incorrect packet length check that allows an integer overflow when handling large payload sizes on 32-bit systems. This issue leads to failed memory allocation and causes the server process to crash, resulting in a denial of service.

Timeline

dates in UTC
  1. 2025-07-2518:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-11-03 21:37 UTC
Indicators tagged with this CVE, per day0 indicators over 7 days
Block these indicators
  • Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2025-5449?format=txt
  • CSV export: https://api.ismalicious.com/edl/cve/CVE-2025-5449?format=csv
  • TAXII collection of exploited CVEs
  • The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD
Libssh
BranchAffectedFixed in
0.11= 0.11.0no fix published
0.11= 0.11.1no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Products declared by the CNA8 products

As redhat, the CNA that assigned this CVE, declared them in the CVE record; versions as written.

2 more products in the CVE record.

Source: the CNA record (CVE Program), © The MITRE Corporation,CVE Terms of UseCVE recordupdated 2026-08-31

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • libsshUbuntu:24.04:LTSall versions · fixed in 0.10.6-2ubuntu0.1
  • libsshUbuntu:22.04:LTSall versions · fixed in 0.9.6-2ubuntu0.22.04.4
  • libsshopenSUSE:Tumbleweedall versions · fixed in 0.11.2-1.1
  • libsshMinimOSall versions · fixed in 0.11.2-r0and 1 other package
  • libsshMageia:9all versions · fixed in 0.10.6-1.1.mga9
  • libsshDebian:14all versions · fixed in 0.11.2-1
  • libsshDebian:13all versions · fixed in 0.11.2-1
  • libsshAlpine:v3.24all versions · fixed in 0.11.2-r0

4 more package ranges on OSV.dev

Vendor advisories

  • CVE-2025-5449 Red Hat Product Security

    libssh: Integer Overflow in libssh SFTP Server Packet Length Validation Leading to Denial of Service

Full record on NVD

Fix

Advisories and patches

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof-of-concept repositories
none listed
PoC-in-GitHub
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Published
2025-07-25
Last Modified
2026-08-31
NVD status
Modified
GitHub Advisory
GHSA-q9x7-4rf7-4xq2

Frequently asked questions

What is CVE-2025-5449?

A flaw was found in the SFTP server message decoding logic of libssh. The issue occurs due to an incorrect packet length check that allows an integer overflow when handling large payload sizes on 32-bit systems. This issue leads to failed memory allocation and causes the server process to crash, resulting in a denial of service.

Is CVE-2025-5449 actively exploited?

Active exploitation of CVE-2025-5449 has not been confirmed. Its EPSS score was 1.0% on 2026-11-03, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2025-5449?

CVE-2025-5449 has a CVSS v3 base score of 6.5 (MEDIUM severity), with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.

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Sources for this record