CVE-2026-92972

Description

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.

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