CVE-2025-66405

Portkey.ai Gateway is a blazing fast AI Gateway with integrated guardrails. Prior to 1.14.0, the gateway determined the destination baseURL by prioritizing the value in the x-portkey-custom-host request header. The proxy route then appends the client-specified path to perform an external fetch. This can be maliciously used by users for SSRF attacks. This vulnerability is fixed in 1.14.0.

CVSS 4.0

6.9CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

CVSS 3.1

9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS

0.4% chance of exploitation in the next 30 days; higher than 30% of CVEs (scores of 2026-10-25)

CWE

CWE-918

Published

2025-12-01

Modified

2026-10-18

Record from

the NVD, synced 2026-10-19

Affected

• portkey:gateway

Packages (OSV)

References

• https://github.com/Portkey-AI/gateway/commit/b5a7825ba5f4e6918deb32d9969899ce2229a885
• https://github.com/Portkey-AI/gateway/pull/1372
• https://github.com/Portkey-AI/gateway/security/advisories/GHSA-hhh5-2cvx-vmfp

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