Vulnerability in Go Standard Library Net/http
CVE-2025-58186
Despite HTTP headers having a default limit of 1MB, the number of cookies that can be parsed does not have a limit. By sending a lot of very small cookies such as "a=;", an attacker can make an HTTP server allocate a large amount of structs, causing large memory consumption.
EPSS: 0.005 (42.2th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L.
Affected products
- Go Standard Library Net/http — versions 0, 1.25.0
References
Frequently asked questions
- What is CVE-2025-58186?
- CVE-2025-58186 is a medium-severity vulnerability in Go Standard Library Net/http, classified under CWE-400: UNCONTROLLED RESOURCE CONSUMPTION. CVSS score: 5.3/10. Published 2025-10-29.
- How severe is CVE-2025-58186?
- Medium severity. CVSS v3 base score is 5.3 out of 10.