SGLang through 0.5.19 in prefill/decode disaggregation mode with Mooncake KV transfer backend fails to validate bootstrap_room values, allowing unbounded transfer state allocation. Unauthenticated attackers can reach the decode engine's POST /generate endpoint and submit arbitrary bootstrap_room values to exhaust prefill process memory until out-of-memory termination.
Attack Parameters
Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Attack Requirements
None
No additional conditions
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed
Impact Assessment
Confidentiality
None
No data leak
Integrity
None
No data modification
Availability
High
Complete denial of service
CVSS Vector v4.0
Weakness Type (CWE)
Vulnerable Products 1
| Configuration | From (including) | Up to (excluding) |
|---|---|---|
|
Lmsys Sglang
cpe:2.3:a:lmsys:sglang:*:*:*:*:*:*:*:*
|
— |
<= 0.5.19
|
References 7
https://github.com/sgl-project/sglang
disclosure@vulncheck.com
https://github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/disaggrega…
disclosure@vulncheck.com
https://github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/disaggrega…
disclosure@vulncheck.com
https://github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/managers/i…
disclosure@vulncheck.com
https://github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/managers/s…
disclosure@vulncheck.com
https://github.com/sgl-project/sglang/issues/39428
disclosure@vulncheck.com
https://www.vulncheck.com/advisories/sglang-through-0.5.19-unbounded-memory-all…
disclosure@vulncheck.com