Description
e621ng versions before 26.09.16 pass untrusted request parameters directly to Rails url_for in PaginatorComponent and controller navigation links, allowing attackers to redirect pagination and navigation controls to attacker-controlled origins. Attackers can supply host, protocol, and port query parameters that are interpreted as URL generation options, causing pagination links to point to malicious domains while the initial page loads from the legitimate site.
References6
- github.com/e621ng/e621ng
- github.com/e621ng/e621ng/blob/26.09.02/app/components/paginator…
- github.com/e621ng/e621ng/commit/e1a3930bf1750b02a23843ec88c33e2…
- github.com/e621ng/e621ng/pull/2518
- github.com/e621ng/e621ng/releases/tag/26.09.16
- www.vulncheck.com/advisories/e621ng-before-26.09.16-open-redire…
Metrics
- CVSS 3.1
-
6.1
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N - CVSS 4.0
-
5.3
MEDIUM
Score source: CNA
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:L/VI:L/VA:N/SC:L/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - EPSS — exploit probability
- 0% percentile: 27 · as of 9 November 2026
- CWE
- CWE-601
Could this be exploited in your environment?
A patch closes the known hole. A penetration test shows what an attacker can still reach — with proof.