CVE-2024-25629: c-ares Out-of-bounds Read — Fix

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.

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CVSS v3.1 Score

4.4

MEDIUM

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-127 CWE-127

CWE-125 Out-of-bounds Read

Affected Products

Vendor	Product	Versions
c-ares	c-ares	< 1.27.0
fedoraproject	fedora	All
fedoraproject	fedora	All
fedoraproject	fedora	All

References

Advisories & Patches

https://github.com/c-ares/c-ares/commit/a804c04ddc8245fc8adf0e92368709639125e183 https://github.com/c-ares/c-ares/security/advisories/GHSA-mg26-v6qh-x48q https://github.com/c-ares/c-ares/commit/a804c04ddc8245fc8adf0e92368709639125e183 https://github.com/c-ares/c-ares/security/advisories/GHSA-mg26-v6qh-x48q

Other References

https://lists.fedoraproject.org/archives/list/[email protected]/message/2P76QYINQNPEHUTEEDOUYIRZ2X6UVZ5K/ https://lists.fedoraproject.org/archives/list/[email protected]/message/CSCMTSPDIE2UHU34TIXQQHZ6JTE3Y3VF/ https://lists.fedoraproject.org/archives/list/[email protected]/message/GX37LFPFQ3T6FFMMFYQTEGIQXXN7F27U/ https://lists.fedoraproject.org/archives/list/[email protected]/message/2P76QYINQNPEHUTEEDOUYIRZ2X6UVZ5K/ https://lists.fedoraproject.org/archives/list/[email protected]/message/CSCMTSPDIE2UHU34TIXQQHZ6JTE3Y3VF/ https://lists.fedoraproject.org/archives/list/[email protected]/message/GX37LFPFQ3T6FFMMFYQTEGIQXXN7F27U/

Frequently Asked Questions

What is CVE-2024-25629? +

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. It has a CVSS v3.1 base score of 4.4 (MEDIUM).

How severe is CVE-2024-25629? +

CVE-2024-25629 has a CVSS v3.1 score of 4.4 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.

What products are affected by CVE-2024-25629? +

CVE-2024-25629 affects products from c-ares, fedoraproject, specifically: c-ares, fedora. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2024-25629? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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