Vulnerability-Lookup

GHSA-6JPG-FR24-WPVF

Vulnerability from github – Published: 2026-03-26 21:31 – Updated: 2026-03-27 00:31

Details

A flaw was found in libssh. A remote attacker, by controlling client configuration files or known_hosts files, could craft specific hostnames that when processed by the match_pattern() function can lead to inefficient regular expression backtracking. This can cause timeouts and resource exhaustion, resulting in a Denial of Service (DoS) for the client.

Severity ?

2.2 (Low)


                  
                    CVSS:3.0/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L

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{
  "affected": [],
  "aliases": [
    "CVE-2026-0967"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-1333"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-03-26T21:17:00Z",
    "severity": "LOW"
  },
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  "id": "GHSA-6jpg-fr24-wpvf",
  "modified": "2026-03-27T00:31:20Z",
  "published": "2026-03-26T21:31:27Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-0967"
    },
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      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2026-0967"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2436981"
    },
    {
      "type": "WEB",
      "url": "https://www.libssh.org/2026/02/10/libssh-0-12-0-and-0-11-4-security-releases"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L",
      "type": "CVSS_V3"
    }
  ]
}

CVE-2026-0967 (GCVE-0-2026-0967)

Vulnerability from cvelistv5 – Published: 2026-03-26 20:06 – Updated: 2026-04-02 17:33

Title

Libssh: libssh: denial of service via inefficient regular expression processing

Summary

A flaw was found in libssh. A remote attacker, by controlling client configuration files or known_hosts files, could craft specific hostnames that when processed by the `match_pattern()` function can lead to inefficient regular expression backtracking. This can cause timeouts and resource exhaustion, resulting in a Denial of Service (DoS) for the client.

Severity ?

2.2 (Low)


                        
                          CVSS:3.0/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:N/A:L

CWE

CWE-1333 - Inefficient Regular Expression Complexity

Assigner

redhat

References

URL

Tags

	https://access.redhat.com/security/cve/CVE-2026-0967	vdb-entryx_refsource_REDHAT
	https://bugzilla.redhat.com/show_bug.cgi?id=2436981	issue-trackingx_refsource_REDHAT
	https://www.libssh.org/2026/02/10/libssh-0-12-0-a…

Impacted products

Vendor

Product

Version

Red Hat

Red Hat Enterprise Linux 10

cpe:/o:redhat:enterprise_linux:10

Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6
Red Hat	Red Hat Enterprise Linux 7	cpe:/o:redhat:enterprise_linux:7
Red Hat	Red Hat Enterprise Linux 8	cpe:/o:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 9	cpe:/o:redhat:enterprise_linux:9
Red Hat	Red Hat OpenShift Container Platform 4	cpe:/a:redhat:openshift:4

Date Public ?

2026-02-10 18:47

Credits

Red Hat would like to thank Jakub Jelen (libssh) and Kang Yang for reporting this issue.

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Sightings

Author	Source	Type	Date

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.

Action not permitted

GHSA-6JPG-FR24-WPVF

CVE-2026-0967 (GCVE-0-2026-0967)

Tags

Sightings

Nomenclature