CVE-2025-13836
7.5 HIGHWhen reading an HTTP response from a server, if no read amount is specified, the default behavior will be to use Content-Length
Published: 2025-12-01 · Last updated: 2026-05-18
Severity and scoring
- CVSS
- 7.5 HIGH
- Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- CWE
- CWE-400
Affected products
| Vendor | Product |
|---|---|
| python | python |
Description
When reading an HTTP response from a server, if no read amount is specified, the default behavior will be to use Content-Length. This allows a malicious server to cause the client to read large amounts of data into memory, potentially causing OOM or other DoS.
Source: NVD
References
- [NVD]https://nvd.nist.gov/vuln/detail/CVE-2025-13836
- [Patch]https://github.com/python/cpython/commit/14b1fdb0a94b96f86fc7b86671ea9582b8676628
- [Patch]https://github.com/python/cpython/commit/289f29b0fe38baf2d7cb5854f4bb573cc34a6a15
- [Patch]https://github.com/python/cpython/commit/4ce27904b597c77d74dd93f2c912676021a99155
- [Patch]https://github.com/python/cpython/commit/5a4c4a033a4a54481be6870aa1896fad732555b5
- [Patch]https://github.com/python/cpython/commit/5dc101675fd22918facbbe0fecdc821502beaaf0
- [Patch]https://github.com/python/cpython/commit/afc40bdd3dd71f343fd9016f6d8eebbacbd6587c
- [Patch]https://github.com/python/cpython/issues/119451
- [Patch]https://github.com/python/cpython/pull/119454
- [Vendor advisory]https://mail.python.org/archives/list/security-announce@python.org/thread/OQ6G7MKRQIS3OAREC3HNG3D2DPOU34XO/
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