High severity · published Oct 27, 2026
CVE-2026-58205
GRR has a Reflected XSS issue
New
8.1
CVSS
–
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
GR
GRR · JeromeDevome
< 4.5.0 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-58205
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-58205
github.com
https://github.com/JeromeDevome/GRR/commit/4ef77f91818215c1f8e0f06023d89257dfd61c68
github.com
https://github.com/JeromeDevome/GRR/security/advisories/GHSA-r6x2-w38j-vvq2
github.com
https://github.com/JeromeDevome/GRR/tree/v4.5.0
More from GRR
9.1
CVE-2026-58256
GRR vulnerable to Remote Code Execution Via PHP Code Injection
7.2
CVE-2026-58257
GRR vulnerable to Arbitrary File Read and Deletion
