CVE-2025-48945
CVE-2025-48945 is a high-severity vulnerability with a CVSS 4.0 base score of 8.2. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-416.
Key facts
- Severity: High (CVSS 4.0 base score 8.2)
- EPSS exploit prediction: 0% (31st percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2025-28273
- Weakness: CWE-416
- Published:
- Last modified:
Description
pycares is a Python module which provides an interface to c-ares. c-ares is a C library that performs DNS requests and name resolutions asynchronously. Prior to version 4.9.0, pycares is vulnerable to a use-after-free condition that occurs when a Channel object is garbage collected while DNS queries are still pending. This results in a fatal Python error and interpreter crash. The vulnerability has been fixed in pycares 4.9.0 by implementing a safe channel destruction mechanism.
Frequently asked questions
- What is CVE-2025-48945?
- pycares is a Python module which provides an interface to c-ares. c-ares is a C library that performs DNS requests and name resolutions asynchronously. Prior to version 4.9.0, pycares is vulnerable to a use-after-free condition that occurs when a Channel object is garbage collected while DNS queries are still pending. This results in a fatal Python error and interpreter crash. The vulnerability has been fixed in pycares 4.9.0 by implementing a safe channel destruction mechanism.
- How severe is CVE-2025-48945?
- CVE-2025-48945 has a CVSS 4.0 base score of 8.2, rated high severity.
- Is CVE-2025-48945 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (31st percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2025-48945?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- Does CVE-2025-48945 have an EU (EUVD) identifier?
- Yes. CVE-2025-48945 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-28273.
- When was CVE-2025-48945 published?
- CVE-2025-48945 was published on 2025-06-20 and last updated on 2026-06-17.
References
- https://github.com/aio-libs/aiodns/commit/f259a6e3650555157af53ac2b39f2ff545321d55
- https://github.com/aio-libs/aiodns/releases/tag/v3.5.0
- https://github.com/saghul/pycares/commit/ebfd7d71eb8e74bc1057a361ea79a5906db510d4
- https://github.com/saghul/pycares/releases/tag/v4.9.0
- https://github.com/saghul/pycares/security/advisories/GHSA-5qpg-rh4j-qp35
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