CVE-2026-93838
mediumSGLang versions through 0.5.20 contain an unbounded memory allocation vulnerability in handle_staging_req() that fails to validate chunk_idx from ZMQ STAGING_R…
SGLang versions through 0.5.20 contain an unbounded memory allocation vulnerability in handle_staging_req() that fails to validate chunk_idx from ZMQ STAGING_REQ frames in prefill/decode disaggregation deployments. Attackers with access to the decode engine's internal ZMQ rank port can send a frame with an extremely large chunk_idx value, causing the scheduler to allocate memory until the system runs out and terminates the process.
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://github.com/sgl-project/sglang disclosure@vulncheck.com
- https://github.com/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/common... disclosure@vulncheck.com
- https://github.com/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/common... disclosure@vulncheck.com
- https://github.com/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/common... disclosure@vulncheck.com
- https://github.com/sgl-project/sglang/issues/39764 disclosure@vulncheck.com
- https://www.vulncheck.com/advisories/sglang-through-0.5.20-unbounded-memory-allocation-via... disclosure@vulncheck.com
- https://github.com/sgl-project/sglang/issues/39764 134c704f-9b21-4f2e-91b3-4a467353bcc0