CVE-2026-28428 json
Talishar: Authentication Bypass via Empty authKey Parameter Allows Unauthenticated Game Actions
published 2026-03-06 8 mo ago modified 2026-06-17 4 mo ago also EUVD-2026-9981
- cvss
- 5.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 28%
- public exploits
- 0
- none known
Summary
Talishar is a fan-made Flesh and Blood project. Prior to commit a9c218e, an authentication bypass vulnerability in Talishar's game endpoint validation logic allows any unauthenticated attacker to perform authenticated game actions — including sending chat messages and submitting game inputs — by supplying an empty authKey parameter (authKey=). The server-side validation uses a loose comparison that accepts an empty string as a valid credential, while correctly rejecting non-empty but incorrect keys. This asymmetry means the authentication mechanism can be completely bypassed without knowing any valid token. This issue has been patched in commit a9c218e.
Patch / fix
- talishar talishar a9c218efa37756c9e7eed056fbff6ee03f79aefc
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- 8 mo ago
Exploit prediction
0.35% chance of exploitation in the next 30 days, higher than 28% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- github.com https://github.com/Talishar/Talishar/security/advisories/GHSA-2659-p579-wv83 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 5.3 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N |
Affected products
- Talishar Talishar
Classification
- Weakness
-
- CWE-287 Improper Authentication
References
Sources
- CVE List CVE-2026-28428
- NVD CVE-2026-28428
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.