CVE-2020-14343
Published: 09 February 2021
A vulnerability was discovered in the PyYAML library in versions before 5.4, where it is susceptible to arbitrary code execution when it processes untrusted YAML files through the full_load method or with the FullLoader loader. Applications that use the library to process untrusted input may be vulnerable to this flaw. This flaw allows an attacker to execute arbitrary code on the system by abusing the python/object/new constructor. This flaw is due to an incomplete fix for CVE-2020-1747.
Priority
Medium
CVSS 3 base score: 9.8
Status
| Package | Release | Status |
|---|---|---|
|
pyyaml Launchpad, Ubuntu, Debian |
Upstream |
Released
(5.4.1)
|
| Ubuntu 21.04 (Hirsute Hippo) |
Released
(5.3.1-3ubuntu1)
|
|
| Ubuntu 20.10 (Groovy Gorilla) |
Released
(5.3.1-2ubuntu0.1)
|
|
| Ubuntu 20.04 LTS (Focal Fossa) |
Released
(5.3.1-1ubuntu0.1)
|
|
| Ubuntu 18.04 LTS (Bionic Beaver) |
Not vulnerable
(code not present)
|
|
| Ubuntu 16.04 ESM (Xenial Xerus) |
Not vulnerable
(code not present)
|
|
| Ubuntu 14.04 ESM (Trusty Tahr) |
Not vulnerable
(code not present)
|
|
|
Patches: Upstream: https://github.com/yaml/pyyaml/commit/7adc0db3f613a82669f2b168edd98379b83adb3c |
||
Notes
| Author | Note |
|---|---|
| sbeattie | incomplete fix of CVE-2020-1747 |
| mdeslaur | FullLoader was introduced in 5.1. FullLoader should not be used on untrusted input. |
References
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-14343
- https://github.com/yaml/pyyaml/wiki/PyYAML-yaml.load(input)-Deprecation
- https://ubuntu.com/security/notices/USN-4940-1
- NVD
- Launchpad
- Debian