CVE-2020-14343
Published: 9 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.
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. |
Priority
Status
| Package | Release | Status |
|---|---|---|
|
pyyaml Launchpad, Ubuntu, Debian |
groovy |
Released
(5.3.1-2ubuntu0.1)
|
| bionic |
Not vulnerable
(code not present)
|
|
| focal |
Released
(5.3.1-1ubuntu0.1)
|
|
| trusty |
Not vulnerable
(code not present)
|
|
| xenial |
Not vulnerable
(code not present)
|
|
| hirsute |
Released
(5.3.1-3ubuntu1)
|
|
| upstream |
Released
(5.4.1)
|
|
|
Patches: upstream: https://github.com/yaml/pyyaml/commit/7adc0db3f613a82669f2b168edd98379b83adb3c |
||
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 9.8 |
| Attack vector | Network |
| Attack complexity | Low |
| Privileges required | None |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |