Netatalk Security Advisory
- Subject
- Heap out-of-bounds write in uams_pam.c
- CVE ID
- CVE-2024-38439
- Date of Publishing
- 2024/06/28
- Affected Netatalk Versions
- 3.2.0
3.0.0 - 3.1.18
1.5.0 - 2.4.0 - Summary
- Lack of user input validation can lead to an out-of-bounds heap write
Description
This vulnerability arises due to a lack of validation for the length field after parsing user-provided data, leading to an out-of-bounds heap write of one byte (\0). Under specific configurations, this can result in an out-of-bounds write to the metadata of the next heap block, potentially allowing an attacker to execute code in the root context.
The vulnerability is located in the FPLoginExt operation of Netatalk's afpd daemon, in the afp_mapname function found in /etc/uams/uams_pam.c. It may be triggered when logging in with the Clear Text user authentication module.
The vulnerable code paths are thought to have been added in the version 1.5.0 release cycle of Netatalk.
Patch Availability
Apply the patch with git hash 77b5d99 to hotfix your local Netatalk deployment.
Additionally, Netatalk 2.4.1, 3.1.19, and 3.2.1 have been released which include the security patch. Netatalk administrators are advised to upgrade to this version or apply the patch as soon as possible.
CVSS Calculation
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L (7.3)
Workaround
Disable the uams_clrtxt.so authentication module in your afp.conf file.
Credits
- Vulnerability found and reported by:
- flysoar
- Patch developed by:
- Daniel Markstedt of the Netatalk team
