CVE-2025-62408 | c-ares has a Use After Free vulnerability when connection is cleaned up after error

c-ares is an asynchronous resolver library. Versions 1.32.3 through 1.34.5 terminate a query after maximum attempts when using read_answer() and process_answer(), which can cause a Denial of Service. This issue is fixed in version 1.34.6.

Published: 2025-12-08 Last update: 2026-02-02 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2025-62408 is rated Low Risk (25.2/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.02%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2025-62408

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-02-24 0.05% 0.02% -0.03%
2 2025-12-14 0.04% 0.05% +0.01%
3 2025-12-09 — 0.04% —

Full EPSS history (3 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2025-62408

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.9 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.2 3.6 [email protected]

Weakness enumeration for CVE-2025-62408

OS Trackers for CVE-2025-62408

vendor priority summary link
alpine — CVE-2025-62408: 1 source package rows (c-ares); 11 state rows across 5 repos (3.20-main, 3.21-main, 3.22-main, 3.23-main, edge-main); fixed 4, open 7. https://security.alpinelinux.org/vuln/CVE-2025-62408
debian unimportant CVE-2025-62408 unimportant priority: Debian including 1 source packages (c-ares), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2025-62408
redhat medium — https://access.redhat.com/security/cve/CVE-2025-62408
suse medium CVE-2025-62408 severity moderate: SUSE including 12 source package names (c-ares, c-ares-devel, …), 86 product×package rows across 30 product lines (SLES-LTSS-TERADATA 15 SP2, SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS, … (30 product lines)): Known Not Affected 79, Fixed 7. https://www.suse.com/security/cve/CVE-2025-62408/
ubuntu medium CVE-2025-62408 medium priority: Ubuntu including 1 source packages (c-ares), 8 status rows across 8 suites (bionic, focal, jammy, noble, plucky, questing, upstream, xenial): not-affected 5, released 3. https://ubuntu.com/security/CVE-2025-62408

Affected software / configurations for CVE-2025-62408

Vendor Product Version Raw CPE
c-ares c-ares >= 1.32.3, < 1.34.6 cpe:2.3:a:c-ares:c-ares:*:*:*:*:*:*:*:*

References for CVE-2025-62408

cvelogic Threat Intelligence