CVE-2026-25680
Description
A flaw was found in golang.org/x/net/html. A remote attacker could provide specially crafted HTML, which, when parsed by the affected component, would consume excessive CPU resources. This could lead to a Denial of Service (DoS) condition, making the system unavailable to legitimate users.
Statement
Red Hat rates this issue as Moderate with RH CVSS 6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H). A flaw was found in golang.org/x/net/html where parsing crafted HTML can consume excessive CPU time, leading to denial of service. Exploitation requires user interaction (a victim application parsing attacker-controlled HTML). Most Red Hat products that bundle golang.org/x/net do not use the html parser to process untrusted HTML in their supported execution paths.
Mitigation
Update affected Go applications to use golang.org/x/net version 0.55.0 or later. As a workaround, do not use golang.org/x/net/html to parse untrusted HTML content, or enforce timeouts on HTML parsing operations. Applications that do not parse arbitrary HTML are not affected.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | N/A | 6.5 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | Required | N/A | Required |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | None |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Resource Consumption (CPU); DoS: Resource Consumption (Memory); DoS: Resource Consumption (Other); Reduce Performance
This issue can make the product perform more slowly. If an attacker can influence the number of iterations in the loop, then this performance problem might allow a denial of service by consuming more platform resources than intended.
Frequently Asked Questions
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