CVE-2025-9648

CVE-2025-9648 is a high-severity vulnerability with a CVSS 4.0 base score of 8.7. 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-158.

Key facts

Description

A vulnerability in the CivetWeb library's function mg_handle_form_request allows remote attackers to trigger a denial of service (DoS) condition. By sending a specially crafted HTTP POST request containing a null byte in the payload, the server enters an infinite loop during form data parsing. Multiple malicious requests will result in complete CPU exhaustion and render the service unresponsive to further requests. This issue was fixed in commit 782e189. This issue affects only the library, standalone executable pre-built by vendor is not affected.

Frequently asked questions

What is CVE-2025-9648?
A vulnerability in the CivetWeb library's function mg_handle_form_request allows remote attackers to trigger a denial of service (DoS) condition. By sending a specially crafted HTTP POST request containing a null byte in the payload, the server enters an infinite loop during form data parsing. Multiple malicious requests will result in complete CPU exhaustion and render the service unresponsive to further requests. This issue was fixed in commit 782e189. This issue affects only the library, standalone executable pre-built by vendor is not affected.
How severe is CVE-2025-9648?
CVE-2025-9648 has a CVSS 4.0 base score of 8.7, rated high severity.
Is CVE-2025-9648 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (49th percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-9648?
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-2025-9648 have an EU (EUVD) identifier?
Yes. CVE-2025-9648 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-31569.
When was CVE-2025-9648 published?
CVE-2025-9648 was published on 2025-09-29 and last updated on 2026-06-17.

References

Other CWE-158 vulnerabilities

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