CVE-2026-59842 (GCVE-0-2026-59842)

Vulnerability from cvelistv5 – Published: 2026-07-21 11:08 – Updated: 2026-08-19 04:57
VLAI
Title
Libssh: libssh: information disclosure via short gssapi curve25519 public key
Summary
A flaw was found in libssh. During server-side GSSAPI key exchange, a client-supplied Curve25519 public key shorter than the expected length is copied without proper length validation, leading to an out-of-bounds heap read. This could allow a remote unauthenticated attacker to disclose small amounts of server memory.
Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-22 14:00 UTC
CWE
Assigner
References
URL Tags
https://access.redhat.com/errata/RHSA-2026:42922 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:55855 vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/security/cve/CVE-2026-59842 vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2498168 issue-trackingx_refsource_REDHAT
Impacted products
Vendor Product Version CPE status
Red Hat Red Hat Enterprise Linux 10 Unaffected: 0:0.12.0-3.el10_2 , < * (rpm)
    cpe:/o:redhat:enterprise_linux:10.2
Create a notification for this product.
Red Hat Red Hat Hardened Images Unaffected: 0.12.1-4.hum1 , < * (rpm)
    cpe:/a:redhat:hummingbird:1
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 8     cpe:/o:redhat:enterprise_linux:8
Create a notification for this product.
Red Hat Red Hat Enterprise Linux 9     cpe:/o:redhat:enterprise_linux:9
Create a notification for this product.
Date Public
2026-07-21 11:03
Credits
Red Hat would like to thank Haruki Oyama, Yi Lin, and nevv for reporting this issue.
Show details on NVD website
To clipboard 

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        "dateReserved": "2026-07-07T15:40:24.560Z",
        "dateUpdated": "2026-08-19T04:57:33.551Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



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Tags
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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.