SGLang through 0.5.20 Denial of Service via Duplicate bootstrap_room
Priority HIGH 77CWE-694Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA.
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.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00582 48th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| sgl-project | sglang | up to 0.5.20 | — | No fix listed | CNA |
- sglang Vendorsgl-project Affected up to 0.5.20 Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2026-102634
- 2026-10-03 Alias added: GHSA-mjgp-hgfr-77jq
References
Other 6
- GitHub Issue #40125
- https://github.com/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/common/conn.py#L392-L393
- https://github.com/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/mooncake/conn.py#L2760-L2764
- https://github.com/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/disaggregation/decode.py#L942
- https://github.com/sgl-project/sglang/blob/v0.5.20/python/sglang/srt/managers/io_struct.py#L281
- https://github.com/sgl-project/sglang
More sgl-project vulnerabilities
- TI-2026-76247 Denial of service in SGLang expert-distribution recording endpoint CVSS 4.0HIGH 8.7
- TI-2026-70996 SGLang disables decompression bomb check, enabling denial of service CVSS 4.0HIGH 8.7
- TI-2026-70994 SGLang Memory Exhaustion DoS via Qwen-VL Video Preprocessing CVSS 4.0HIGH 8.7
- TI-2026-70993 Decompression amplification in SGLang load_audio exhausts memory CVSS 4.0HIGH 8.7
- TI-2026-75290 Code injection in SGLang debug dumper filter CVSS 4.0CRITICAL 9.2
- TI-2026-76467 Server-side request forgery in SGLang via bootstrap_host and bootstrap_port CVSS 4.0MEDIUM 6.9
Sources
- CVE-2026-102634 · CVE Program
- CVE-2026-102634 · NVD
- FIRST EPSS
- GHSA-mjgp-hgfr-77jq · GitHub Advisory Database · CC BY 4.0
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