GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.7 before 18.7.4, and 18.8 before 18.8.4 that could have allowed an unauthenticated user to cause denial of service through CPU exhaustion by submitting specially crafted markdown files that trigger exponential processing in markdown preview.

The version of GitLab installed on the remote host is affected by a vulnerability, as follows:

  - GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.7 before 18.7.4, and 18.8     before 18.8.4 that could have allowed an unauthenticated user to cause denial of service through CPU     exhaustion by submitting specially crafted markdown files that trigger exponential processing in markdown     preview. (CVE-2026-1456)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - GitLab has remediated an issue in GitLab CE/EE affecting all versions from 18.7 before 18.7.4, and 18.8     before 18.8.4 that could have allowed an unauthenticated user to cause denial of service through CPU     exhaustion by submitting specially crafted markdown files that trigger exponential processing in markdown     preview. (CVE-2026-1456)

Note that Nessus relies on the presence of the package as reported by the vendor.

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by multiple vulnerabilities as referenced in the 9d9940e7-071c-11f1-93ca-2cf05da270f3 advisory.

    Gitlab reports:
    Incomplete Validation issue in Web IDE impacts GitLab CE/EE     Denial of Service issue in GraphQL introspection impacts GitLab CE/EE     Denial of Service issue in JSON validation middleware impacts GitLab CE/EE     Cross-site Scripting issue in Code Flow impacts GitLab CE/EE     HTML Injection issue in test case titles impacts GitLab CE/EE     Denial of Service issue in Markdown processor impacts GitLab CE/EE     Denial of Service issue in Markdown Preview impacts GitLab CE/EE     Denial of Service issue in dashboard impacts GitLab EE     Server-Side Request Forgery issue in Virtual Registry impacts GitLab EE     Improper Validation issue in diff parser impacts GitLab CE/EE     Server-Side Request Forgery issue in Git repository import impacts GitLab CE/EE     Authorization Bypass issue in iterations API impacts GitLab EE     Missing Authorization issue in GLQL API impacts GitLab CE/EE     Stored HTML Injection issue in project label impacts GitLab CE/EE     Authorization Bypass issue in Pipeline Schedules API impacts GitLab CE/EE

Tenable has extracted the preceding description block directly from the FreeBSD security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Severity
298876	GitLab 18.7 < 18.7.4 / 18.8 < 18.8.4 (CVE-2026-1456)	Nessus	CGI abuses	high
298763	Linux Distros Unpatched Vulnerability : CVE-2026-1456	Nessus	Misc.	high
298644	FreeBSD : Gitlab -- vulnerabilities (9d9940e7-071c-11f1-93ca-2cf05da270f3)	Nessus	FreeBSD Local Security Checks	critical

Detections

Analytics

CVE-2026-1456

high

Tenable Plugins

high

high

critical