libssh up to 0.11.1 base64 Conversion memory corruption

CVSS Meta Temp Score
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CTI Interest Score
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4.9$0-$5k0.00

Summaryinfo

A vulnerability marked as critical has been reported in libssh up to 0.11.1. The affected element is an unknown function of the component base64 Conversion Handler. This manipulation causes memory corruption. This vulnerability appears as CVE-2025-4877. There is no available exploit. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in libssh up to 0.11.1. Affected by this vulnerability is an unknown code of the component base64 Conversion Handler. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

There's a vulnerability in the libssh package where when a libssh consumer passes in an unexpectedly large input buffer to ssh_get_fingerprint_hash() function. In such cases the bin_to_base64() function can experience an integer overflow leading to a memory under allocation, when that happens it's possible that the program perform out of bounds write leading to a heap corruption. This issue affects only 32-bits builds of libssh.

The advisory is shared at libssh.org. This vulnerability is known as CVE-2025-4877. The exploitation appears to be easy. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 241379 (SUSE SLED15 / SLES15 / openSUSE 15 Security Update : libssh (SUSE-SU-2025:02229-1)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 0.11.2 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (241379) and CERT Bund (WID-SEC-2025-1423). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

  • Red Hat Enterprise Linux
  • Fedora Linux
  • Ubuntu Linux
  • SUSE Linux
  • Oracle Linux
  • NetApp AFF
  • NetApp ActiveIQ Unified Manager
  • RESF Rocky Linux
  • Dell Avamar
  • NetApp FAS
  • Open Source libssh
  • IBM App Connect Enterprise
  • Dell NetWorker
  • Dell Secure Connect Gateway
  • Red Hat OpenShift
  • Meinberg LANTIME
  • IBM Security Verify Access
  • IBM QRadar SIEM

Productinfo

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.0
VulDB Meta Temp Score: 4.9

VulDB Base Score: 5.5
VulDB Temp Score: 5.3
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.5
CNA Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: Partially

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 241379
Nessus Name: SUSE SLED15 / SLES15 / openSUSE 15 Security Update : libssh (SUSE-SU-2025:02229-1)

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: libssh 0.11.2

Timelineinfo

06/28/2025 Advisory disclosed
06/28/2025 +0 days VulDB entry created
05/19/2026 +325 days VulDB entry last update

Sourcesinfo

Advisory: libssh.org
Status: Confirmed

CVE: CVE-2025-4877 (🔒)
GCVE (CVE): GCVE-0-2025-4877
GCVE (VulDB): GCVE-100-314353
CERT Bund: WID-SEC-2025-1423 - libssh: Mehrere Schwachstellen

Entryinfo

Created: 06/28/2025 13:27
Updated: 05/19/2026 16:30
Changes: 06/28/2025 13:27 (51), 07/05/2025 12:45 (2), 10/18/2025 19:46 (7), 10/20/2025 10:45 (1), 11/03/2025 19:33 (1), 11/28/2025 11:21 (1), 11/28/2025 16:26 (1), 12/18/2025 17:55 (1), 01/25/2026 17:01 (1), 05/19/2026 16:30 (13)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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