CVE-2026-93688

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 v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
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

Configurations

No configuration.

History

18 Sep 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-18 16:17

Updated : 2026-09-22 20:43

NVD link : CVE-2026-93688

Mitre link : CVE-2026-93688

CVE.ORG link : CVE-2026-93688

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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