CVE-2021-3737
Estado: ModificadaAlta (7.5)—
A flaw was found in python. An improperly handled HTTP response in the HTTP client code of python may allow a remote attacker, who controls the HTTP server, to make the client script enter an infinite loop, consuming CPU time. The highest threat from this vulnerability is to system availability.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 7.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 12%
- Percentil entre todas las CVEs puntuadas: 96
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (17)
Canonical — Ubuntu LinuxFedoraproject — FedoraNetapp — HCINetapp — Management Services FOR Element SoftwareNetapp — Netapp XCP SMBNetapp — Ontap Select Deploy Administration UtilityNetapp — XCP NFSOracle — Communications Cloud Native Core Binding Support FunctionOracle — Communications Cloud Native Core Network Exposure FunctionOracle — Communications Cloud Native Core PolicyPython — PythonRedhat — Codeready Linux BuilderRedhat — Codeready Linux Builder FOR IBM Z SystemsRedhat — Codeready Linux Builder FOR Power Little EndianRedhat — Enterprise LinuxRedhat — Enterprise Linux FOR IBM Z SystemsRedhat — Enterprise Linux FOR Power Little Endian
CWE
- CWE-835
- CWE-400, CWE-835
Referencias
- https://bugs.python.org/issue44022
- https://bugzilla.redhat.com/show_bug.cgi?id=1995162
- https://github.com/python/cpython/pull/25916
- https://github.com/python/cpython/pull/26503
- https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
- https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
- https://python-security.readthedocs.io/vuln/urllib-100-continue-loop.html
- https://security.netapp.com/advisory/ntap-20220407-0009/
- https://ubuntu.com/security/CVE-2021-3737
- https://www.oracle.com/security-alerts/cpujul2022.html
- https://bugs.python.org/issue44022
- https://bugzilla.redhat.com/show_bug.cgi?id=1995162
- https://github.com/python/cpython/pull/25916
- https://github.com/python/cpython/pull/26503
- https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
- https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
- https://lists.debian.org/debian-lts-announce/2024/11/msg00024.html
- https://lists.debian.org/debian-lts-announce/2024/12/msg00000.html
- https://python-security.readthedocs.io/vuln/urllib-100-continue-loop.html
- https://security.netapp.com/advisory/ntap-20220407-0009/
- https://ubuntu.com/security/CVE-2021-3737
- https://www.oracle.com/security-alerts/cpujul2022.html
JSON original (NVD)
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