CVE-2026-69186
Fixed in a distro release EPSS <1%CVSS 5.3
c-ares is an asynchronous resolver library. Prior to 1.34.7, ares_dns_parse() trusts the attacker-controlled ANCOUNT, NSCOUNT, and ARCOUNT fields before confirming that the DNS response contains enough bytes for the claimed records. Because process_answer() invokes parsing before transaction ID and question validation, a malicious DNS response can cause ares_dns_record_rr_prealloc() and ares_array_set_size() to reserve disproportionate heap memory for a tiny message. Repeated responses create large allocation and release cycles that can degrade or deny name resolution, without causing memory corruption or information disclosure. This issue is fixed in version 1.34.7.
Products: c-ares
Distro releases
| Release | Package | Fixed in |
|---|---|---|
| Debian 13 | c-ares | no fix |
| Debian 14 | c-ares | 1.34.7-1 |
| Red Hat hummingbird 1 | c-ares | 0:1.34.8-2.hum1 |
| Red Hat hummingbird 1 | c-ares-devel | 0:1.34.8-2.hum1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Micro 5.3 | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Micro 5.4 | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Micro 5.5 | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Module for Basesystem 15 SP7 | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Server 15 SP4-LTSS | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Server 15 SP5-LTSS | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Server 15 SP6-LTSS | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Server 16.0 | c-ares | 1.34.8-160000.1.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | c-ares | 1.34.8-150000.3.29.1 |
| SUSE Linux Enterprise Server for SAP applications 16.0 | c-ares | 1.34.8-160000.1.1 |
| SUSE Linux Micro 6.0 | c-ares | 1.34.8-1.1 |
| SUSE Linux Micro 6.1 | c-ares | 1.34.8-slfo.1.1_1.1 |
| Ubuntu 22.04 LTS | c-ares | 1.18.1-1ubuntu0.22.04.4 |
| Ubuntu 24.04 LTS | c-ares | 1.27.0-1.0ubuntu1.1 |
| Ubuntu 26.04 LTS | c-ares | 1.34.6-1ubuntu0.2 |
| Ubuntu Pro 16.04 LTS | c-ares | 1.10.0-3ubuntu0.2+esm4 |
| Ubuntu Pro 18.04 LTS | c-ares | 1.14.0-1ubuntu0.2+esm3 |
| Ubuntu Pro 20.04 LTS | c-ares | 1.15.0-1ubuntu0.5+esm1 |
| openSUSE Leap 16.0 | c-ares | 1.34.8-160000.1.1 |
| openSUSE Tumbleweed | c-ares | 1.34.8-1.1 |