Denial of Service in CivetWeb
Published Sep 29, 2025
8.7
HIGHCVSS 4.0
EPSS 0.76%
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.
Affected products
-
Affected
- ≥ 1.10, ≤ 1.16
Unaffected
- ≥ 0, < 1.08
No data.
No data.
Red Hat Advanced Cluster Security 4.7
advanced-cluster-security/rhacs-collector-rhel8:4.7
Fixed · RHSA-2025:23248
Red Hat Advanced Cluster Security 4.8
advanced-cluster-security/rhacs-collector-rhel8:4.8
Fixed · RHSA-2025:22179
Red Hat Advanced Cluster Security 4.9
advanced-cluster-security/rhacs-collector-rhel8:4.9
Fixed · RHSA-2025:21929
Red Hat Advanced Cluster Security 4
advanced-cluster-security/rhacs-collector-slim-rhel8
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Advanced Cluster Security 4.7 | advanced-cluster-security/rhacs-collector-rhel8:4.7 | Fixed | RHSA-2025:23248 |
| Red Hat Advanced Cluster Security 4.8 | advanced-cluster-security/rhacs-collector-rhel8:4.8 | Fixed | RHSA-2025:22179 |
| Red Hat Advanced Cluster Security 4.9 | advanced-cluster-security/rhacs-collector-rhel8:4.9 | Fixed | RHSA-2025:21929 |
| Red Hat Advanced Cluster Security 4 | advanced-cluster-security/rhacs-collector-slim-rhel8 | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
On Red Hat systems a denial of service in the CivetWeb application does not pose a broader availability risk to the host.
Red Hat mitigation
Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.
References (9)
- https://access.redhat.com/security/cve/CVE-2025-9648 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=2400107 Issue Tracking
- https://cert.pl/en/posts/2025/09/CVE-2025-9648 third-party-advisory
- https://euvd.enisa.europa.eu/vulnerability/EUVD-2025-31569 Advisory
- https://github.com/civetweb/civetweb product
- https://github.com/civetweb/civetweb/commit/782e18903515f43bafbf2e668994e82bdfa51133 patch
- https://github.com/civetweb/civetweb/issues/1348 issue-tracking
- https://nvd.nist.gov/vuln/detail/CVE-2025-9648
- https://www.cve.org/CVERecord?id=CVE-2025-9648
Change history (0)
No recorded changes yet.
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