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

Vulnerability from cvelistv5 – Published: 2025-09-09 11:55 – Updated: 2025-11-21 07:29
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
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)
Date Public ?
2025-09-09 00:00
Credits
Red Hat would like to thank Francesco Rollo for reporting this issue.
Show details on NVD website
To clipboard 

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Taxonomy of the tags.




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

Author Source Type Date Other

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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • 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.



Detection rules are retrieved from Rulezet.