CVE-2026-69184 (CVSS 7.5)

Description

c-ares is an asynchronous resolver library. Prior to 1.34.7, ares_dns_name_parse() enforces backward DNS compression pointers but does not bound the total pointer hops or assembled name length. A malicious DNS server can send a response containing a long descending pointer chain and many resource records whose NAME or RDATA fields refer to the chain, causing repeated decompression work that grows quadratically with message size. A single crafted response can stall the single-threaded c-ares event loop and deny DNS resolution, without causing memory corruption or information disclosure. This issue is fixed in version 1.34.7.

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CVSS v3.1 Score

7.5

HIGH

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

EPSS — Exploit Prediction

0.0068

Probability of exploitation

0.51%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-407 CWE-407

References

Other References

https://github.com/c-ares/c-ares/commit/5c8341ba6ff3a8e4e4dfd616f8ed0418838b8b7b https://github.com/c-ares/c-ares/commit/f1288bbc70e9a1e0a77134c2382157e52d326aea https://github.com/c-ares/c-ares/pull/1164 https://github.com/c-ares/c-ares/pull/1210 https://github.com/c-ares/c-ares/releases/tag/v1.34.7 https://github.com/c-ares/c-ares/security/advisories/GHSA-pjmc-gx33-gc76

Frequently Asked Questions

What is CVE-2026-69184? +

c-ares is an asynchronous resolver library. Prior to 1.34.7, ares_dns_name_parse() enforces backward DNS compression pointers but does not bound the total pointer hops or assembled name length. A malicious DNS server can send a response containing a long descending pointer chain and many resource records whose NAME or RDATA fields refer to the chain, causing repeated decompression work that grows quadratically with message size. A single crafted response can stall the single-threaded c-ares event loop and deny DNS resolution, without causing memory corruption or information disclosure. This issue is fixed in version 1.34.7. It has a CVSS v3.1 base score of 7.5 (HIGH).

How severe is CVE-2026-69184? +

CVE-2026-69184 has a CVSS v3.1 score of 7.5 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0068, placing it in the 1th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-69184? +

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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