---
title: "CVE-2026-32301: Centrifugo: SSRF via unverified JWT claims interpolated into dynamic JWKS endpoint URL"
url: https://erroneo.us/security/cve/CVE-2026-32301/
description: "CVE-2026-32301 (github.com/centrifugal/centrifugo/v6 (Go)): Centrifugo is an open-source scalable real-time messaging server. Prior to 6.7.0, Centrifugo is…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-03-12
date_modified: 2026-03-27
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-32301"
kev: false
cvss: 9.3
epss: 0.00372
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-32301: Centrifugo: SSRF via unverified JWT claims interpolated into dynamic JWKS endpoint URL

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.4% , percentile 30: FIRST’s model estimates a 0.4% chance of exploitation activity in the next 30 days, higher than 30% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Remotely reachable with no login and no user interaction. If the vulnerable service is exposed to the internet, prioritize it.
- Only applies if your dependency tree includes github.com/centrifugal/centrifugo/v6 (Go) <= 6.6.2, fixed in 6.7.0 ; github.com/centrifugal/centrifugo (Go) <= 2.4.0, no fixed version listed ; github.com/centrifugal/centrifugo/v3 (Go) <= 3.2.3, no fixed version listed ; github.com/centrifugal/centrifugo/v4 (Go) <= 4.1.5, no fixed version listed . Check your lockfile, including transitive dependencies.

## What it is

Centrifugo is an open-source scalable real-time messaging server. Prior to 6.7.0, Centrifugo is vulnerable to Server-Side Request Forgery (SSRF) when configured with a dynamic JWKS endpoint URL using template variables (e.g. {{tenant}}). An unauthenticated attacker can craft a JWT with a malicious iss or aud claim value that gets interpolated into the JWKS fetch URL before the token signature is verified, causing Centrifugo to make an outbound HTTP request to an attacker-controlled destination. This vulnerability is fixed in 6.7.0.

## Affected packages

- Go `github.com/centrifugal/centrifugo/v6` <= 6.6.2 → fixed: 6.7.0
- Go `github.com/centrifugal/centrifugo` <= 2.4.0 → fixed: none listed
- Go `github.com/centrifugal/centrifugo/v3` <= 3.2.3 → fixed: none listed
- Go `github.com/centrifugal/centrifugo/v4` <= 4.1.5 → fixed: none listed
- Go `github.com/centrifugal/centrifugo/v5` <= 5.4.9 → fixed: none listed

## Affected products (CVE record)

- centrifugal centrifugo: < 6.7.0

## Severity

- GitHub_M CVSS 3.1: 9.3 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N`
- GitHub CVSS 3.1: 9.3 `CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:L/A:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable yes , technical impact partial .
- FIRST EPSS (model of 2026-10-21): 0.37% probability of exploitation activity in the next 30 days; percentile 30.

## Sources

- [GitHub Advisory GHSA-j77h-rr39-c552](https://github.com/advisories/GHSA-j77h-rr39-c552)
- [CVE.org record CVE-2026-32301](https://www.cve.org/CVERecord?id=CVE-2026-32301)
- [NVD entry CVE-2026-32301](https://nvd.nist.gov/vuln/detail/CVE-2026-32301)
- [github.com](https://github.com/centrifugal/centrifugo/security/advisories/GHSA-j77h-rr39-c552)
- [pkg.go.dev](https://pkg.go.dev/vuln/GO-2026-4702)

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Source page: https://erroneo.us/security/cve/CVE-2026-32301/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt