Auth bypass in Sgl-Project Sglang
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.
Vulnerability class: Broken Authentication
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.6 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:H.
EPSS exploit prediction
EPSS: 0.005 (40.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 41st percentile — 40.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000
Affected products
Weakness classification (CWE)
References
- github.com/sgl-project/sglang/issues/39400 (issue-tracking)
- github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/disaggregation/com… (technical-description)
- github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/disaggregation/com… (technical-description)
- github.com/sgl-project/sglang (product)
- www.vulncheck.com/advisories/sglang-through-0.5.19-unauthenticated-route-poison… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-92972?
- CVE-2026-92972 is a high-severity vulnerability in Sgl-Project Sglang, classified under Missing Authentication for Critical Function. CVSS score: 8.6/10. Published 2026-09-17.
- How severe is CVE-2026-92972?
- High severity. CVSS v3 base score is 8.6 out of 10.