CVE-2021-3733
Estado: ModificadaMedia (6.5)—
There's a flaw in urllib's AbstractBasicAuthHandler class. An attacker who controls a malicious HTTP server that an HTTP client (such as web browser) connects to, could trigger a Regular Expression Denial of Service (ReDOS) during an authentication request with a specially crafted payload that is sent by the server to the client. The greatest threat that this flaw poses is to application availability.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- Puntuación base: 6.5
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 4.67%
- Percentil entre todas las CVEs puntuadas: 92
- 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 (20)
Fedoraproject — Extra Packages FOR Enterprise LinuxFedoraproject — FedoraNetapp — HCI Compute Node FirmwareNetapp — Management Services FOR Element Software AND Netapp HCINetapp — Ontap Select Deploy Administration UtilityNetapp — Solidfire, Enterprise SDS & HCI Storage NodePython — PythonRedhat — Codeready Linux BuilderRedhat — Codeready Linux Builder FOR IBM Z SystemsRedhat — Codeready Linux Builder FOR Power Little EndianRedhat — Enterprise LinuxRedhat — Enterprise Linux EUSRedhat — Enterprise Linux FOR IBM Z SystemsRedhat — Enterprise Linux FOR IBM Z Systems EUSRedhat — Enterprise Linux FOR Power Little EndianRedhat — Enterprise Linux FOR Power Little Endian EUSRedhat — Enterprise Linux Server AUSRedhat — Enterprise Linux Server FOR Power Little Endian Update Services FOR SAP SolutionsRedhat — Enterprise Linux Server TUSRedhat — Enterprise Linux Server Update Services FOR SAP Solutions
CWE
- CWE-400
- CWE-400
Referencias
- https://bugs.python.org/issue43075
- https://bugzilla.redhat.com/show_bug.cgi?id=1995234
- https://github.com/python/cpython/commit/7215d1ae25525c92b026166f9d5cac85fb
- https://github.com/python/cpython/pull/24391
- https://lists.debian.org/debian-lts-announce/2023/05/msg00024.html
- https://lists.debian.org/debian-lts-announce/2023/06/msg00039.html
- https://security.netapp.com/advisory/ntap-20220407-0001/
- https://ubuntu.com/security/CVE-2021-3733
- https://bugs.python.org/issue43075
- https://bugzilla.redhat.com/show_bug.cgi?id=1995234
- https://github.com/python/cpython/commit/7215d1ae25525c92b026166f9d5cac85fb
- https://github.com/python/cpython/pull/24391
- 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/2024/12/msg00000.html
- https://security.netapp.com/advisory/ntap-20220407-0001/
- https://ubuntu.com/security/CVE-2021-3733
JSON original (NVD)
Mostrar
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