CVE-2026-93688

Description

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.

CVSS Vector

References

• https://github.com/sgl-project/sglang
• https://github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/disaggregation/mooncake/conn.py#L1988-L1990
• https://github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/disaggregation/mooncake/conn.py#L2118-L2119
• https://github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/managers/io_struct.py#L281
• https://github.com/sgl-project/sglang/blob/v0.5.19/python/sglang/srt/managers/scheduler.py#L2672-L2690
• https://github.com/sgl-project/sglang/issues/39428
• https://www.vulncheck.com/advisories/sglang-through-0.5.19-unbounded-memory-allocation-via-bootstrap-room