CVE-2026-33630

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Source
https://cve.org/CVERecord?id=CVE-2026-33630
Import Source
https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2026-33630.json
JSON Data
https://api.test.osv.dev/v1/vulns/CVE-2026-33630
Aliases
  • GHSA-6wfj-rwm7-3542
Downstream
Related
Published
2026-09-03T18:42:28Z
Modified
2026-09-14T18:26:52Z
Severity
  • 7.5 (High) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
Summary
c-ares : Use-after-free / double-free in c-ares query-completion handling, remotely triggerable via ares_getaddrinfo() over TCP
Details

c-ares is an asynchronous resolver library. From ver 1.32.3 until 1.34.7, a use-after-free / double-free in c-ares' query-completion handling. The same flaw — a query's callback being invoked while the query is still linked in the channel's internal lookup structures — is present at multiple points in the resend/finish path (timeout handling, response handling, and query dispatch). If the query, or for ares_getaddrinfo() the owning host_query, is freed as a side effect of that callback, it is then accessed and/or freed a second time. This vulnerability is fixed in ver 1.34.7.

Database specific 
{
    "cna_assigner":  "GitHub_M",
    "cwe_ids":  [
        "CWE-415",
        "CWE-416"
    ],
    "osv_generated_from":  "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33630.json"
}
References

Affected packages

Git / github.com/c-ares/c-ares

Affected ranges

Type
GIT
Repo
https://github.com/c-ares/c-ares
Events
Introduced
5899dea2b1f8e78f311aaed7db98b82b5537c9f9
Fixed
1fa3b86a0b8d18fe7b60f3228a01d770feb026bc
Fixed
d823199b688052dcdc1646f2ab4cb8c16b1c644a
Fixed
d63b7de3a3568d14ab1351374b205365aed51cca
Database specific
Show details 
{
    "extracted_events":  [
        {
            "introduced":  "1.32.3"
        },
        {
            "fixed":  "1.34.7"
        }
    ],
    "source":  [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

Database specific

source 
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vanir_signatures_modified 
"2026-09-11T08:58:49Z"