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TI-2024-16857 Aliases CVE-2024-25629

c-ares out of bounds read in ares__read_line()

Priority LOW 25CWE-127Published · Updated

Key facts

Attack vector
Local
Privileges required
Low
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 6 fixed, 5 without a fix

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-125 and the CVSS impact.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00352 29th percentileScored 2026-11-07
Fix Partial c-ares (c-ares): 1.27.0Red Hat: 9 advisoriesRed Hat: 6 fixed, 5 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
c-aresc-aresbefore 1.27.01.27.0Patch availableCNA
  • c-ares Vendorc-ares Affected before 1.27.0 Fixed in 1.27.0 Patch available CNA

CPE configurations NVD · 4

CPEVersionsRoleVendor
cpe:2.3:a:c-ares:c-ares:*:*:*:*:*:*:*:*before 1.27.0Vulnerablec-ares
cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:*38VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:*39VulnerableFedoraproject
cpe:2.3:o:fedoraproject:fedora:40:*:*:*:*:*:*:*40VulnerableFedoraproject
  • cpe:2.3:a:c-ares:c-ares:*:*:*:*:*:*:*:* Versions before 1.27.0 Vulnerable ·c-ares
  • cpe:2.3:o:fedoraproject:fedora:38:*:*:*:*:*:*:* Versions 38 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:39:*:*:*:*:*:*:* Versions 39 Vulnerable ·Fedoraproject
  • cpe:2.3:o:fedoraproject:fedora:40:*:*:*:*:*:*:* Versions 40 Vulnerable ·Fedoraproject

Remediation

  • Fix · CNA c-ares (c-ares) Fixed in 1.27.0

Red Hat 9 advisories

  • RHSA-2024:4721 Released 2024-07-23 · Red Hat rating Moderate
    nodejs security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.0) nodejs-1:16.20.2-9.el9_0, nodejs-docs-1:16.20.2-9.el9_0, nodejs-full-i18n-1:16.20.2-9.el9_0 +2
  • RHSA-2024:4559 Released 2024-07-16 · Red Hat rating Moderate
    nodejs security update
    • Red Hat Enterprise Linux AppStream EUS (v.9.2) nodejs-1:16.20.2-6.el9_2.3, nodejs-docs-1:16.20.2-6.el9_2.3, nodejs-full-i18n-1:16.20.2-6.el9_2.3 +2
  • RHSA-2024:4249 Released 2024-07-02 · Red Hat rating Low
    c-ares security update
    • Red Hat Enterprise Linux BaseOS (v. 8) c-ares-1.13.0-11.el8_10, c-ares-devel-1.13.0-11.el8_10
Show 6 more Red Hat advisories
  • RHSA-2024:3842 Released 2024-06-11 · Red Hat rating Low
    c-ares security update
    • Red Hat Enterprise Linux AppStream (v. 9) c-ares-devel-1.19.1-2.el9_4
    • Red Hat Enterprise Linux BaseOS (v. 9) c-ares-1.19.1-2.el9_4
  • RHSA-2024:2910 Released 2024-05-20 · Red Hat rating Important
    nodejs security update
    • Red Hat Enterprise Linux AppStream (v. 9) nodejs-1:16.20.2-8.el9_4, nodejs-docs-1:16.20.2-8.el9_4, nodejs-full-i18n-1:16.20.2-8.el9_4 +2
  • RHSA-2024:2853 Released 2024-05-15 · Red Hat rating Important
    nodejs:20 security update
    • Red Hat Enterprise Linux AppStream (v. 9) nodejs-1:20.12.2-2.module+el9.4.0+21731+46b5b8a7.aarch64::nodejs:20, nodejs-1:20.12.2-2.module+el9.4.0+21731+46b5b8a7.ppc64le::nodejs:20, nodejs-1:20.12.2-2.module+el9.4.0+21731+46b5b8a7.s390x::nodejs:20 +20
  • RHSA-2024:2780 Released 2024-05-09 · Red Hat rating Important
    nodejs:18 security update
    • Red Hat Enterprise Linux AppStream (v. 8) nodejs-1:18.20.2-1.module+el8.9.0+21767+537f34ee.aarch64::nodejs:18, nodejs-1:18.20.2-1.module+el8.9.0+21767+537f34ee.ppc64le::nodejs:18, nodejs-1:18.20.2-1.module+el8.9.0+21767+537f34ee.s390x::nodejs:18 +20
  • RHSA-2024:2778 Released 2024-05-09 · Red Hat rating Important
    nodejs:20 security update
    • Red Hat Enterprise Linux AppStream (v. 8) nodejs-1:20.12.2-2.module+el8.9.0+21743+0b3f1be2.aarch64::nodejs:20, nodejs-1:20.12.2-2.module+el8.9.0+21743+0b3f1be2.ppc64le::nodejs:20, nodejs-1:20.12.2-2.module+el8.9.0+21743+0b3f1be2.s390x::nodejs:20 +20
  • RHSA-2024:2779 Released 2024-05-09 · Red Hat rating Important
    nodejs:18 security update
    • Red Hat Enterprise Linux AppStream (v. 9) nodejs-1:18.20.2-2.module+el9.4.0+21742+692df1ea.aarch64::nodejs:18, nodejs-1:18.20.2-2.module+el9.4.0+21742+692df1ea.ppc64le::nodejs:18, nodejs-1:18.20.2-2.module+el9.4.0+21742+692df1ea.s390x::nodejs:18 +20

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat Enterprise Linux 10AffectedNo fix yet
Red Hat Enterprise Linux 6AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 7AffectedNo fix planned: Out of support scope
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Red Hat Software CollectionsAffectedNo fix yet: Fix deferred
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2024:2778, RHSA-2024:2780
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2024:2779, RHSA-2024:2853, RHSA-2024:2910, RHSA-2024:3842
Red Hat Enterprise Linux AppStream E4S (v.9.0)Fixed RHSA-2024:4721
Red Hat Enterprise Linux AppStream EUS (v.9.2)Fixed RHSA-2024:4559
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2024:4249
Red Hat Enterprise Linux BaseOS (v. 9)Fixed RHSA-2024:3842
Not affected: 1 product
  • Red Hat Enterprise Linux 10

Timeline

  1. 2026-10-02 Threatist record created from CVE-2024-25629

References

Patch 1

Advisory 1

Other 3

  • TI-2020-14305 Buffer overflow vulnerability in c-ares before 1_16_1 thru 1_17_0 via function… CVSS 3.1MEDIUM 5.9
  • TI-2016-04481 Heap-based buffer overflow in the ares_create_query function in c-ares 1.x before 1.12.0… CVSS 3.1CRITICAL 9.8
  • TI-2017-14601 The c-ares function `ares_parse_naptr_reply()`, which is used for parsing NAPTR… CVSS 3.1HIGH 7.5
  • TI-2025-38675 c-ares has a Use After Free vulnerability when connection is cleaned up after error CVSS 3.1MEDIUM 5.9
  • TI-2020-11224 Buffer overflow in c-ares CVSS 3.1LOW 3.3

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences