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TI-2024-10111 Aliases CVE-2024-10907GHSA-qg86-f892-m4hj

Denial of Service (DoS) via Multipart Boundary in lm-sys/fastchat

Priority HIGH 72CWE-835Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.0 · CNA. Fix status from CNA and GitHub. Impact type from CWE-835.

Summary

In lm-sys/fastchat Release v0.2.36, the server fails to handle excessive characters appended to the end of multipart boundaries. This flaw can be exploited by sending malformed multipart requests with arbitrary characters at the end of the boundary. Each extra character is processed in an infinite loop, leading to excessive resource consumption and a complete denial of service (DoS) for all users. The vulnerability is unauthenticated, meaning no user login or interaction is required for an attacker to exploit this issue.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.007 53rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
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

VendorProductAffected versionsFixed inStatusSource
lm-syslm-sys/fastchatup to latest—No fix listedCNA
—fschat (PyPI)up to 0.2.36—No fix listedGHSA-qg86-f892-m4hj
  • lm-sys/fastchat Vendorlm-sys Affected up to latest Fixed in — No fix listed CNA
  • fschat (PyPI) Vendor— Affected up to 0.2.36 Fixed in — No fix listed GHSA-qg86-f892-m4hj

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:lm-sys:fastchat:0.2.36:*:*:*:*:*:*:*0.2.36Vulnerablelm-sys
  • cpe:2.3:a:lm-sys:fastchat:0.2.36:*:*:*:*:*:*:* Versions 0.2.36 Vulnerable ·lm-sys

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-10907
  2. 2026-10-03 Alias added: GHSA-qg86-f892-m4hj

References

Exploit 1

Advisory 1

Other 1

  • TI-2024-09320 SSRF in POST /worker_generate_stream API endpoint in lm-sys/fastchat CVSS 3.0CRITICAL 9.3
  • TI-2024-11482 Server Side Request Forgery in lm-sys/fastchat CVSS 3.0HIGH 7.5
  • TI-2024-10750 Server-Side Request Forgery in lm-sys/fastchat CVSS 3.0HIGH 7.5
  • TI-2024-10115 Denial of Service in lm-sys/fastchat CVSS 3.0HIGH 7.5
  • TI-2024-10112 Open Redirect in lm-sys/fastchat CVSS 3.0MEDIUM 6.1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences