CVE-2026-102634 SGLang through 0.5.20 Denial of Service via Duplicate bootstrap_room
Unauthenticated attackers can crash scheduler processes or hang requests in SGLang by sending duplicate bootstrap_room values in prefill/decode disaggregation mode.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-102634?
CVE-2026-102634 is a high-severity denial of service vulnerability in sgl-project sglang, published on 29 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
SGLang through 0.5.20 in prefill/decode disaggregation mode fails to validate duplicate bootstrap_room fields in /generate requests with Mooncake KV transfer backend. Unauthenticated attackers can send concurrent requests with identical bootstrap_room values to crash scheduler processes or hang other users' requests until transfer timeout.
Weakness: CWE-694
Which versions are affected by CVE-2026-102634?
Linux distribution packages (1)
python-sglang openSUSE:Tumbleweed | All versions | 0.5.20-2.1 |
How do I fix CVE-2026-102634?
Apply the vendor's patch.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-102634 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-102634 exists.
Sources
Also known as GHSA-mjgp-hgfr-77jq, openSUSE-SU-2026:11947-1.