Skip to content
Fencer Intel
medium 6.1

CVE-2025-52552 json

FastGPT LastRoute Parameter on Login Page Vulnerable to Open Redirect and DOM-based XSS

published last yr. modified 4mo ago also EUVD-2025-18916

cvss
6.1
version 3.1, NVD
cisa kev
Not listed
not in CISA's catalog
epss
0.3%
EPSS 0.3% chance of exploitation in 30 days, percentile 18%
public exploits
0
none known

Summary

FastGPT is an AI Agent building platform. Prior to version 4.9.12, the LastRoute Parameter on login page is vulnerable to open redirect and DOM-based XSS. Improper validation and lack of sanitization of this parameter allows attackers execute malicious JavaScript or redirect them to attacker-controlled sites. This issue has been patched in version 4.9.12.

Patch / fix

  • fastgpt fastgpt 4.9.12

Is CVE-2025-52552 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.

Check with Fencer

CISA SSVC

Exploitation
Proof of concept is public
Automatable
no
Technical impact
partial
Assessed
last yr.

Exploit prediction

0.27% chance of exploitation in the next 30 days, higher than 18% of all scored CVEs (FIRST EPSS, 2026-11-09).

Exploits and checks

  • github.com https://github.com/labring/FastGPT/security/advisories/GHSA-r976-rfrv-q24m referenced PoC, tagged "exploit" by a source, unverified

CVSS scores

assigned by version score vector
CNA 4.0 5.5 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H
CNA 4.0 5.5 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:N/VI:N/VA:N/SC:H/SI:H/SA:H/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
NVD 3.1 6.1 CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Affected products

  • labring FastGPT

Classification

Weakness
  • CWE-601 URL Redirection to Untrusted Site
  • CWE-79 Improper Neutralization of Input During Web Page Generation

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.