CVE-2026-102634 json
SGLang through 0.5.20 Denial of Service via Duplicate bootstrap_room
published last mo. modified last mo. also EUVD-2026-89029
- cvss
- 7.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 48%
- public exploits
- 0
- none known
Summary
SGLang through 0.5.20 in prefill/decode disaggregation mode fails to validate duplicate bootstrap_room fields in /generate requests with Mooncake KV transfer backend. Unauthenticated attackers can send concurrent requests with identical bootstrap_room values to crash scheduler processes or hang other users' requests until transfer timeout.
Patch / fix
- python-sglang openSUSE Tumbleweed 0.5.20-2.1
opensuse advisories openSUSE-SU-2026:11947-1
Is CVE-2026-102634 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerCISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- yes
- Technical impact
- partial
- Assessed
- last mo.
Exploit prediction
0.58% chance of exploitation in the next 30 days, higher than 48% of all scored CVEs (FIRST EPSS, 2026-11-09).
Exploits and checks
- github.com https://github.com/sgl-project/sglang/issues/40125 referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N |
| CNA | 3.1 | 7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| CNA | 4.0 | 8.7 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |
Affected products
- sgl-project sglang
Classification
- Weakness
-
- CWE-694 Use of Multiple Resources with Duplicate Identifier
References
-
github.com
/sgl-project/sglang/issues/40125
issue-tracking, exploit
-
github.com
/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/common/conn.py#L392-L393
technical-description
-
github.com
/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/mooncake/conn.py#L2760-L2764
technical-description
-
github.com
/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/decode.py#L942
technical-description
-
github.com
/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/managers/io_struct.py#L281
technical-description
-
github.com
/sgl-project/sglang
product
-
vulncheck.com
/advisories/sglang-through-0.5.20-denial-of-service-via-duplicate-bootstrap-room
third-party-advisory
Sources
- CVE List CVE-2026-102634
- NVD CVE-2026-102634
Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.
CPEs and fixed versions use Anchore's correction of NVD's data: Added CPE configurations because not yet analyzed by NVD.