CVE-2022-2309

Public on 2022-07-05
Modified on 2024-03-18
Description
NULL Pointer Dereference allows attackers to cause a denial of service (or application crash). This only applies when lxml is used together with libxml2 2.9.10 through 2.9.14. libxml2 2.9.9 and earlier are not affected. It allows triggering crashes through forged input data, given a vulnerable code sequence in the application. The vulnerability is caused by the iterwalk function (also used by the canonicalize function). Such code shouldn't be in wide-spread use, given that parsing + iterwalk would usually be replaced with the more efficient iterparse function. However, an XML converter that serialises to C14N would also be vulnerable, for example, and there are legitimate use cases for this code sequence. If untrusted input is received (also remotely) and processed via iterwalk function, a crash can be triggered.
Severity
Important severity
Important
CVSS v3 Base Score
7.5
See breakdown

Affected Packages

Platform Package Release Date Advisory Status
Amazon Linux 1 libxml2 Not Affected
Amazon Linux 2 - Core libxml2 Not Affected
Amazon Linux 2023 libxml2 Not Affected
Amazon Linux 1 python-lxml Not Affected
Amazon Linux 2 - Core python-lxml Not Affected
Amazon Linux 2023 python-lxml 2023-02-17 ALAS2023-2023-034 Fixed

CVSS Scores

Score Type Score Vector
Amazon Linux CVSSv3 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
NVD CVSSv2 5.0 AV:N/AC:L/Au:N/C:N/I:N/A:P
NVD CVSSv3 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H