CVE-2026-28428 Talishar: Authentication Bypass via Empty authKey Parameter Allows Unauthenticated Game Actions
Unauthenticated attackers can bypass authentication and perform game actions by supplying an empty authKey parameter due to loose comparison logic.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-28428?
CVE-2026-28428 is a medium-severity authentication bypass vulnerability in Talishar, published on 6 Mar 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
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.
Weakness: CWE-287
Which versions are affected by CVE-2026-28428?
It affects 1 product.
Products include Talishar Talishar.
How do I fix CVE-2026-28428?
No fix has been published for CVE-2026-28428 yet. Limit exposure of the affected software until one is available.
Upgrade, and rotate credentials and sessions that may have been exposed. More about Authentication bypass.
Is CVE-2026-28428 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-28428 exists.
Other vulnerabilities in Talishar
Sources
Also known as GHSA-2659-p579-wv83.