CVE-2026-49998 json
Centrifugo: Dynamic JWKS key cache keyed only by `kid` allows cross-issuer JWT authentication bypass
published 2026-07-01 4 mo ago modified 2026-10-24 15 d ago also EUVD-2026-45015 , GHSA-g6vg-wj8f-48cj , GO-2026-5872
- cvss
- 8.2
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 12%
- public exploits
- 0
- none known
Summary
Centrifugo is an open-source scalable real-time messaging server. Prior to 6.8.1, Centrifugo dynamic JWKS endpoint verification could reuse a key for one allowed issuer to verify a JWT for another allowed issuer because the JWKS cache and singleflight lookup were keyed only by JWT header kid, not by the resolved JWKS endpoint, issuer, audience, or trust-domain namespace, affecting client.token.jwks_public_endpoint, client.subscription_token.jwks_public_endpoint, internal/jwks/cache.go, and internal/jwks/manager.go. This issue is fixed in version 6.8.1.
Patch / fix
- go github.com/centrifugal/centrifugo/v6 6.8.1
- centrifugal centrifugo 6.8.1
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- total
- Assessed
- 3 mo ago
Exploit prediction
0.22% chance of exploitation in the next 30 days, higher than 12% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/centrifugal/centrifugo/security/advisories/GHSA-g6vg-wj8f-48cj referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 8.2 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N |
| GitHub | 3.1 | 8.2 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/centrifugal/centrifugo/v6 | <6.8.1 |
6.8.1 |
| go | github.com/centrifugal/centrifugo/v5 | <=5.4.9 all versions |
no fix listed |
| go | github.com/centrifugal/centrifugo/v4 | <=4.1.5 all versions |
no fix listed |
| go | github.com/centrifugal/centrifugo/v3 | <=3.2.3 all versions |
no fix listed |
| go | github.com/centrifugal/centrifugo | <=2.4.0 all versions |
no fix listed |
Affected products
- centrifugal centrifugo
Classification
- Weakness
-
- CWE-347 Improper Verification of Cryptographic Signature
References
- github.com /centrifugal/centrifugo/pull/1142
- github.com /centrifugal/centrifugo/commit/15d785015c6f318c1b68ea40b813699c9f8bd2c4
-
github.com
/centrifugal/centrifugo/security/advisories/GHSA-g6vg-wj8f-48cj
exploit, web, advisory
- github.com /centrifugal/centrifugo/releases/tag/v6.8.1
-
github.com
/centrifugal/centrifugo
package
Sources
- CVE List CVE-2026-49998
- GitHub Advisory GHSA-g6vg-wj8f-48cj
- NVD CVE-2026-49998
- OSV GO-2026-5872
Fencer Vulns 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.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.