CVE catalog
CVE-2026-53540
Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.31, parse_form() did not validate the Content-Length header before using it to bound its chunked read of the request body. A n
- Severity
- Low · CVSS 3.7
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.34% · Oct 25, 2026
Python-Multipart is a streaming multipart parser for Python. Prior to 0.0.31, parse_form() did not validate the Content-Length header before using it to bound its chunked read of the request body. A negative Content-Length turned the bounded read into a read-until-EOF, so the entire body was loaded into memory in a single read instead of in fixed-size chunks. This vulnerability is fixed in 0.0.31.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | python-multipart | sid | 0.0.32-1 | fixed |
| Debian | python-multipart | forky | 0.0.32-1 | fixed |
| Debian | python-multipart | trixie | 0.0.20-1.1~deb13u1 | vulnerable |
| Debian | python-multipart | bookworm | 0.0.5-3 | vulnerable |
| Cpe | python-multipart | Not reported | Not reported | vulnerable |
| Cpe | python-multipart | Not reported | 0.0.31 | fixed |
| PyPI | python-multipart | Not reported | 0.0.31 | fixed |
| Cpe | python-multipart | Not reported | 0.0.31 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | python-multipart | source | sid | 0.0.32-1 | not yet assigned | Not reported | [1140628] |
| Debian | python-multipart | source | forky | 0.0.32-1 | not yet assigned | Not reported | [1140628] |
| Debian | python-multipart | source | trixie | (unfixed) | not yet assigned | Not reported | [1140628] |
| Debian | python-multipart | source | bookworm | (unfixed) | not yet assigned | Not reported | [1140628] |
| Cpe | python-multipart | cpe | Not reported | 0.0.31 | Not reported | Not reported | Not reported |
| PyPI | python-multipart | PyPI | Not reported | 0.0.31 | Not reported | GHSA-V9PG-7XVM-68HF | Not reported |
| Cpe | python-multipart | cpe | Not reported | 0.0.31 | Not reported | NVD-CVE-2026-53540 | Not reported |
Notes
[trixie] python-multipart: Minor issue [bookworm] python-multipart: Minor issue; negative Content-Length unvalidated in parse_form(), which starlette/fastapi do not use
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [python3-multipart]Affected
Source package: [python-multipart]
Details (2)
0.0.5-3· all · bookwormAffected
nvd · python-multipart · debian · bookworm; nvd · python-multipart · debian · 12
0.0.5-3· all · bookwormAffected
nvd · python-multipart · debian · bookworm; nvd · python-multipart · debian · 12
[Debian 13 (Trixie)]
- [python3-python-multipart]Affected
Source package: [python-multipart]
Details (2)
0.0.20-1.1~deb13u1· all · trixieAffected
nvd · python-multipart · debian · 13
0.0.20-1.1~deb13u1· all · trixieAffected
nvd · python-multipart · debian · 13
Observed:
References
- [https://ftp.suse.com/pub/projects/security/csaf/suse-su-2026_22372-1.json]
- [https://github.com/Kludex/python-multipart/security/advisories/GHSA-v9pg-7xvm-68hf]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-53540]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-53540]
- [https://osv.dev/vulnerability/GHSA-v9pg-7xvm-68hf]
- [https://security-tracker.debian.org/tracker/CVE-2026-53540]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-53540.json]
[Debian Security Tracker] · [FIRST EPSS] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX]