Description
c-ares is a C library for asynchronous DNS requests. `ares__read_line()` is used to parse local configuration files such as `/etc/resolv.conf`, `/etc/nsswitch.conf`, the `HOSTALIASES` file, and if using a c-ares version prior to 1.27.0, the `/etc/hosts` file. If any of these configuration files has an embedded `NULL` character as the first character in a new line, it can lead to attempting to read memory prior to the start of the given buffer which may result in a crash. This issue is fixed in c-ares 1.27.0. No known workarounds exist.
References (5)
Core 5
Core References
Mailing List
https://lists.fedoraproject.org/archives/list/[email protected]/message/2P76QYINQNPEHUTEEDOUYIRZ2X6UVZ5K/
Mailing List
https://lists.fedoraproject.org/archives/list/[email protected]/message/CSCMTSPDIE2UHU34TIXQQHZ6JTE3Y3VF/
Mailing List
https://lists.fedoraproject.org/archives/list/[email protected]/message/GX37LFPFQ3T6FFMMFYQTEGIQXXN7F27U/
Vendor Advisory x_refsource_confirm
https://github.com/c-ares/c-ares/security/advisories/GHSA-mg26-v6qh-x48q
Patch x_refsource_misc
https://github.com/c-ares/c-ares/commit/a804c04ddc8245fc8adf0e92368709639125e183
Scores
CVSS v3
4.4
EPSS
0.0006
EPSS Percentile
17.0%
Attack Vector
LOCAL
CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
no
Technical Impact
partial
Details
CWE
CWE-125
CWE-127
Status
published
Products (4)
c-ares/c-ares
< 1.27.0
fedoraproject/fedora
38
fedoraproject/fedora
39
fedoraproject/fedora
40
Published
Feb 23, 2024
Tracked Since
Feb 18, 2026