8.6High
CVE-2026-92972
SGLang through 0.5.19 in prefill/decode disaggregation mode contains an unauthenticated PUT /route endpoint on the prefill bootstrap service that allows attackers to poison the KV transfer routing table. Attackers can supply arbitrary rank_ip and rank_port values to redirect decode workers to attacker-controlled endpoints, causing denial of service or disclosure of KV transfer metadata including session identifiers and tensor-parallel topology parameters.
What this means for your business
- An attacker can use it remotely, over a network, without a login, and without anyone at your company clicking anything.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 8.6 (v3.1)
- Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H- CVSS v4
- 8.8
- Weakness
- CWE-306
- Assigned by
- disclosure@vulncheck.com
Dates
- Published
- 2026-09-17
- Last modified
- 2026-09-17
- Sources
- NVD
References
- https://github.com/sgl-project/sglang
- https://github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/disaggregation/common/conn.py#L1716-L1718
- https://github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/disaggregation/common/conn.py#L1736-L1810
- https://github.com/sgl-project/sglang/issues/39400
- https://www.vulncheck.com/advisories/sglang-through-0.5.19-unauthenticated-route-poisoning-via-put-endpoint