GHSA-g588-cjg3-6g78 Steamworks game clients/servers using P2P authentication vulnerable to denial of service
A malicious game client can cause a denial of service in Steamworks game clients or servers by sending a specific authentication ticket that triggers a panic.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is GHSA-g588-cjg3-6g78?
GHSA-g588-cjg3-6g78 is a denial of service vulnerability in steamworks, published on 5 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
ValidateAuthTicketResponse_t callback data panics when the m_eAuthSessionResponse field is k_EAuthSessionResponseAuthTicketNetworkIdentityFailure. This can lead to denial of service in game clients and servers using the begin_authentication_session API to authenticate players if a malicious game client sends an authentication ticket with a network identity that does not match that of the verifier.Which versions are affected by GHSA-g588-cjg3-6g78?
3 open source packages ship an affected version, including steamworks.
| Package | Affected | Fixed in |
|---|---|---|
steamworks crates.io | All versions | 0.13.1 |
steamworks crates.io | All versions | 0.13.1 |
steamworks crates.io | From 0.0.0-0 | 0.13.1 |
How do I fix GHSA-g588-cjg3-6g78?
Upgrade steamworks to 0.13.1 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is GHSA-g588-cjg3-6g78 being exploited?
There is no known exploitation of GHSA-g588-cjg3-6g78 in the wild and no public exploit code.
Sources
Also known as RUSTSEC-2026-0121.