PYSEC-2026-1395

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Import Source
https://github.com/pypa/advisory-database/blob/main/vulns/fschat/PYSEC-2026-1395.yaml
JSON Data
https://api.osv.dev/v1/vulns/PYSEC-2026-1395
Aliases
Published
2026-07-07T14:34:52.223565Z
Modified
2026-07-07T17:46:29.830975759Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
FastChat Denial of Service vulnerability
Details

A Denial of Service (DoS) vulnerability exists in the file upload feature of lm-sys/fastchat version 0.2.36. The vulnerability is due to improper handling of form-data with a large filename in the file upload request. An attacker can exploit this by sending a payload with an excessively large filename, causing the server to become overwhelmed and unavailable to legitimate users.

References

Affected packages

PyPI / fschat

Package

Affected ranges

Type
ECOSYSTEM
Events
Introduced
0Unknown introduced version / All previous versions are affected
Last affected
0.2.36

Affected versions

0.*
0.1.1
0.1.2
0.1.3
0.1.4
0.1.5
0.1.6
0.1.7
0.1.8
0.1.9
0.1.10
0.2.0
0.2.1
0.2.2
0.2.3
0.2.4
0.2.5
0.2.6
0.2.7
0.2.8
0.2.9
0.2.10
0.2.11
0.2.12
0.2.13
0.2.14
0.2.15
0.2.16
0.2.17
0.2.18
0.2.20
0.2.21
0.2.23
0.2.24
0.2.26
0.2.27
0.2.28
0.2.29
0.2.30
0.2.31
0.2.32
0.2.33
0.2.34
0.2.35
0.2.36

Database specific

source
"https://github.com/pypa/advisory-database/blob/main/vulns/fschat/PYSEC-2026-1395.yaml"