CVE-2026-109227 SGLang through 0.5.21 Memory Exhaustion DoS via Qwen-VL Video Preprocessing
Remote attackers can cause denial of service in SGLang Qwen-VL deployments by submitting high-resolution videos that trigger unbounded memory allocation.
- 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-2026-109227?
CVE-2026-109227 is a high-severity denial of service vulnerability in sgl-project sglang, published on 12 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
SGLang through 0.5.21 contains an unbounded memory allocation vulnerability in preprocess_video in qwen_vl.py that decodes frames at full source resolution before applying max_pixels limits. Remote attackers can submit high-resolution videos to /v1/chat/completions on Qwen-VL deployments, and concurrent requests exhaust worker memory causing denial of service.
Weakness: CWE-770
Which versions are affected by CVE-2026-109227?
How do I fix CVE-2026-109227?
No fix has been published for CVE-2026-109227 yet. Limit exposure of the affected software until one is available.
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-2026-109227 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-109227 exists.
Sources
Also known as GHSA-6h2g-h3jf-2prp.