DEBIAN-CVE-2026-53539
- Source
- https://security-tracker.debian.org/tracker/CVE-2026-53539
- Import Source
- https://storage.googleapis.com/osv-test-debian-osv/debian-cve-osv/DEBIAN-CVE-2026-53539.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/DEBIAN-CVE-2026-53539
- Upstream
- Published
- 2026-06-22T18:16:44Z
- Modified
- 2026-09-01T16:06:50Z
- Severity
-
- 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
- Summary
- [none]
- Details
-
Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.30, when parsing application/x-www-form-urlencoded bodies, QuerystringParser located the field separator with a two step lookup: it first scanned the entire remaining buffer for &, and only when no & existed anywhere ahead did it fall back to scanning for ;. For a body that uses ; as the separator and contains no &, every field iteration performed a full failed & scan over the entire remaining buffer before locating the nearby ;. With N semicolon separated fields in a chunk of size B, this yields O(B^2) byte comparisons per chunk. An attacker can submit a small crafted body of the form a;a;a;... and cause the parser to spend seconds of CPU per request. A handful of concurrent requests can exhaust worker processes. This vulnerability is fixed in 0.0.30.
- References
Affected packages
Debian:12 / python-multipart
Package
- Name
- python-multipart
- Purl
- pkg:deb/debian/python-multipart?arch=source&distro=bookworm
Affected ranges
- Type
- ECOSYSTEM
- Events
-
Introduced0 Unknown introduced version / All previous versions are affected
Debian:13 / python-multipart
Package
- Name
- python-multipart
- Purl
- pkg:deb/debian/python-multipart?arch=source&distro=trixie
Debian:14 / python-multipart
Package
- Name
- python-multipart
- Purl
- pkg:deb/debian/python-multipart?arch=source&distro=forky