CVE-2025-58186: CWE-400: Uncontrolled Resource Consumption in Go standard library net/http
CVE-2025-58186 is a medium severity vulnerability in the Go standard library net/http package. It involves uncontrolled resource consumption due to the lack of a limit on the number of cookies parsed, despite an overall HTTP header size limit of 1MB. An attacker can exploit this by sending many small cookies, causing the server to allocate excessive memory and degrade availability.
AI Analysis
Technical Summary
The vulnerability in the Go standard library's net/http package arises because while HTTP headers have a default size limit of 1MB, there is no limit on the number of cookies parsed. An attacker can send numerous very small cookies (e.g., "a=;") which forces the HTTP server to allocate a large number of internal structures, resulting in significant memory consumption. This is classified under CWE-400: Uncontrolled Resource Consumption. The affected versions include all versions up to 1.25.0. The CVSS v3.1 base score is 5.3 (medium severity), reflecting a network attack vector with low complexity and no privileges or user interaction required, impacting availability only.
Potential Impact
The impact is limited to availability degradation due to excessive memory consumption on the HTTP server. There is no confidentiality or integrity impact. No known exploits are reported in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — no patch or official fix information is provided in the vendor advisory. Users should monitor the Go project advisories for updates. Until a fix is available, consider implementing application-level limits on the number of cookies processed or deploying upstream protections such as web application firewalls that can limit cookie count or size.
CVE-2025-58186: CWE-400: Uncontrolled Resource Consumption in Go standard library net/http
Description
CVE-2025-58186 is a medium severity vulnerability in the Go standard library net/http package. It involves uncontrolled resource consumption due to the lack of a limit on the number of cookies parsed, despite an overall HTTP header size limit of 1MB. An attacker can exploit this by sending many small cookies, causing the server to allocate excessive memory and degrade availability.
CVSS v3.1
Score 5.3medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability in the Go standard library's net/http package arises because while HTTP headers have a default size limit of 1MB, there is no limit on the number of cookies parsed. An attacker can send numerous very small cookies (e.g., "a=;") which forces the HTTP server to allocate a large number of internal structures, resulting in significant memory consumption. This is classified under CWE-400: Uncontrolled Resource Consumption. The affected versions include all versions up to 1.25.0. The CVSS v3.1 base score is 5.3 (medium severity), reflecting a network attack vector with low complexity and no privileges or user interaction required, impacting availability only.
Potential Impact
The impact is limited to availability degradation due to excessive memory consumption on the HTTP server. There is no confidentiality or integrity impact. No known exploits are reported in the wild at this time.
Mitigation Recommendations
Patch status is not yet confirmed — no patch or official fix information is provided in the vendor advisory. Users should monitor the Go project advisories for updates. Until a fix is available, consider implementing application-level limits on the number of cookies processed or deploying upstream protections such as web application firewalls that can limit cookie count or size.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Go
- Date Reserved
- 2025-08-27T14:50:58.691Z
- State
- PUBLISHED
Threat ID: 69029404f29b216d6d5e20bd
Added to database: 10/29/2025, 22:24:04 UTC
Last enriched: 06/03/2026, 21:17:51 UTC
Last updated: 09/10/2026, 19:36:51 UTC
Views: 188
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