Medium 5.3Published Oct 29, 2025

CVE-2025-58186Lack of limit when parsing cookies can cause memory exhaustion in net/http

Updated under an hour ago (Oct 27, 2026, 4:00 PM ET)

Does this affect you?

It affects Go standard library net/http. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

Every CVE for Go standard library net/http

Exploited in the last 30 days

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.

CVSS: 5.3 MEDIUM (v3.1, CISA ADP)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Weakness (CWE): CWE-400
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Go
NVD analysis: Deferred
Record last updated: Nov 4, 2025
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Go standard library net/http go_standard_library:net_http (from the name)	before 1.24.8; from 1.25.0 before 1.25.2	CNA record

References

References

https://go.dev/issue/75672
https://go.dev/cl/709855
https://groups.google.com/g/golang-announce/c/4Emdl2iQ_bI
https://pkg.go.dev/vuln/GO-2025-4012
http://www.openwall.com/lists/oss-security/2025/10/08/1

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.