Netatalk Security Advisory
- Subject
- Heap out-of-bounds write in uams_dhx_pam.c
- CVE ID
- CVE-2024-38440
- Date of Publishing
- 2024/06/28
- Affected Netatalk Versions
- 2.0.0 - 2.4.0
3.0.0 - 3.1.18
3.2.0 - 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 reading metadata of the next heap block, potentially causing a Denial of Service (DoS) under certain heap layouts or with ASAN enabled.
The vulnerable code paths are thought to have been added leading up to the 2.0.0 release of Netatalk, when the user login flow was rewritten to accommodate the AFP v3 protocol specification.
Patch Availability
Apply the patch with git hash 77b5d99007cfef4d73d76fd6f0c26584891608e5 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.
CVSSv3 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_dhx.so authentication module in your afp.conf file.
Credits
- Vulnerability found and reported by:
- flysoar
- Patch developed by:
- Daniel Markstedt of the Netatalk Team