Buffer overflow in Civetweb Project

CVE-2025-55763

Buffer Overflow in the URI parser of CivetWeb 1.14 through 1.16 (latest) allows a remote attacker to achieve remote code execution via a crafted HTTP request. This vulnerability is triggered during request processing and may allow an attacker to corrupt heap memory, potentially leading to denial of service or arbitrary code execution.

Vulnerability class: Buffer Overflow

EPSS: 0.012 (66.3th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2025-55763?
CVE-2025-55763 is a high-severity vulnerability in Civetweb Project, classified under Stack-based Buffer Overflow. CVSS score: 7.5/10. Published 2025-08-29.
How severe is CVE-2025-55763?
High severity. CVSS v3 base score is 7.5 out of 10.
Is CVE-2025-55763 known to be exploited?
3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.