CVE-2025-4877 (GCVE-0-2025-4877)

Vulnerability from cvelistv5 – Published: 2025-08-20 12:19 – Updated: 2026-05-19 13:16
VLAI
Title
Libssh: write beyond bounds in binary to base64 conversion functions
Summary
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.
Severity
4.5 (Medium)
CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
Assigner
References
Impacted products
Vendor Product Version
Affected: 0 , < 0.11.2 (semver)
Red Hat Red Hat Enterprise Linux 9 Unaffected: 0:0.10.4-18.el9 , < * (rpm)
    cpe:/a:redhat:enterprise_linux:9::appstream
    cpe:/o:redhat:enterprise_linux:9::baseos
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Red Hat Red Hat Enterprise Linux 10     cpe:/o:redhat:enterprise_linux:10
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Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
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Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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Red Hat Red Hat Enterprise Linux 8     cpe:/o:redhat:enterprise_linux:8
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Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
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Date Public
2025-06-24 00:00
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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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