CVE-2025-8277 (GCVE-0-2025-8277)

Vulnerability from cvelistv5 – Published: 2025-09-09 11:55 – Updated: 2026-05-19 13:17
VLAI
Title
Libssh: memory exhaustion via repeated key exchange in libssh
Summary
A flaw was found in libssh's handling of key exchange (KEX) processes when a client repeatedly sends incorrect KEX guesses. The library fails to free memory during these rekey operations, which can gradually exhaust system memory. This issue can lead to crashes on the client side, particularly when using libgcrypt, which impacts application stability and availability.
Severity
3.1 (Low)
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-401 - Missing Release of Memory after Effective Lifetime
Assigner
References
Impacted products
Vendor Product Version
Affected: 0.6.0 , < 0.11.3 (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
2025-09-09 00:00
Credits
Red Hat would like to thank Francesco Rollo for reporting this issue.
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Sightings

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  • 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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  • 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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