CVE-2023-6918 (GCVE-0-2023-6918)

Vulnerability from cvelistv5 – Published: 2023-12-18 23:27 – Updated: 2025-11-21 06:23
VLAI
Title
Libssh: missing checks for return values for digests
Summary
A flaw was found in the libssh implements abstract layer for message digest (MD) operations implemented by different supported crypto backends. The return values from these were not properly checked, which could cause low-memory situations failures, NULL dereferences, crashes, or usage of the uninitialized memory as an input for the KDF. In this case, non-matching keys will result in decryption/integrity failures, terminating the connection.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
CWE
Assigner
References
Impacted products
Vendor Product Version
Red Hat Red Hat Enterprise Linux 8 Unaffected: 0:0.9.6-14.el8 , < * (rpm)
    cpe:/o:redhat:enterprise_linux:8::baseos
    cpe:/a:redhat:enterprise_linux:8::appstream
 Create a notification for this product.
Red Hat Red Hat Enterprise Linux 9 Unaffected: 0:0.10.4-13.el9 , < * (rpm)
    cpe:/o:redhat:enterprise_linux:9::baseos
    cpe:/a:redhat:enterprise_linux:9::appstream
 Create a notification for this product.
Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
 Create a notification for this product.
Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
 Create a notification for this product.
Date Public
2023-12-18 00:00
Credits
Red Hat would like to thank Jack Weinstein (<mike.code.bb.h@gmail.com>) for reporting this issue.
Show details on NVD website
To clipboard 

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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

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.