Vulnerability · Published Oct 27, 2026 · Assigned by GitHub_M

CVE-2026-58205GRR has a Reflected XSS issue

High 8.1

In plain English

A high-severity cross-site scripting in GRR from JeromeDevome. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 21% of all known vulnerabilities).

Severity (CVSS 3.1)8.1High

Exploit odds (30 days)0.3%top 78.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

GRR is a resource management and reservation application. Prior to version 4.5.0, `maj.php` reflects the `forcemaj` parameter without adequate escaping when installation files remain accessible. Removal of these files is not automatic. An attacker can craft a URL that executes arbitrary JavaScript in a victim's browser when the victim accesses it. This reflected cross-site scripting can enable phishing, redirection to malicious sites, cookie theft and session hijacking because the authentication cookie is not `HttpOnly`. This issue is fixed in version 4.5.0.

Affected products (as reported)

Vendor	Product	Versions
JeromeDevome	GRR	< 4.5.0

Weakness: CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N

References

https://github.com/JeromeDevome/GRR/security/advisories/GHSA-r6x2-w38j-vvq2 x_refsource_CONFIRM
https://github.com/JeromeDevome/GRR/commit/4ef77f91818215c1f8e0f06023d89257dfd61c68 x_refsource_MISC
https://github.com/JeromeDevome/GRR/tree/v4.5.0 x_refsource_MISC