CVE-2026-42502: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in golang.org/x/net golang.org/x/net/html
CVE-2026-42502 is a medium severity cross-site scripting (XSS) vulnerability in the golang.org/x/net/html package. It arises when parsing arbitrary HTML and rendering it with the Render function, which can produce an unexpected HTML tree. This affects applications that sanitize input HTML before rendering, resulting in improper neutralization of input during web page generation. There is no official patch or remediation guidance available yet, and no known exploits have been reported in the wild.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-42502) in the golang.org/x/net/html package involves improper neutralization of input during web page generation, classified as CWE-79 (Cross-site Scripting). It occurs when the Render function processes arbitrary HTML, potentially producing an unexpected HTML tree that can bypass sanitization efforts. This flaw impacts applications relying on this package for HTML sanitization and rendering. Currently, there is no official fix or remediation guidance from the vendor, and no known exploitation in the wild has been reported.
Potential Impact
The vulnerability allows for cross-site scripting attacks due to improper input neutralization during HTML rendering. This can lead to limited confidentiality and integrity impacts, such as injection of malicious scripts in the rendered HTML. However, no availability impact is noted. No known active exploitation has been reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or remediation guidance is available, users should monitor vendor communications for updates. Until a fix is released, cautious handling of untrusted HTML input and additional application-level sanitization may help reduce risk.
CVE-2026-42502: CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in golang.org/x/net golang.org/x/net/html
Description
CVE-2026-42502 is a medium severity cross-site scripting (XSS) vulnerability in the golang.org/x/net/html package. It arises when parsing arbitrary HTML and rendering it with the Render function, which can produce an unexpected HTML tree. This affects applications that sanitize input HTML before rendering, resulting in improper neutralization of input during web page generation. There is no official patch or remediation guidance available yet, and no known exploits have been reported in the wild.
CVSS v3.1
Score 6.1medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-42502) in the golang.org/x/net/html package involves improper neutralization of input during web page generation, classified as CWE-79 (Cross-site Scripting). It occurs when the Render function processes arbitrary HTML, potentially producing an unexpected HTML tree that can bypass sanitization efforts. This flaw impacts applications relying on this package for HTML sanitization and rendering. Currently, there is no official fix or remediation guidance from the vendor, and no known exploitation in the wild has been reported.
Potential Impact
The vulnerability allows for cross-site scripting attacks due to improper input neutralization during HTML rendering. This can lead to limited confidentiality and integrity impacts, such as injection of malicious scripts in the rendered HTML. However, no availability impact is noted. No known active exploitation has been reported.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Since no official fix or remediation guidance is available, users should monitor vendor communications for updates. Until a fix is released, cautious handling of untrusted HTML input and additional application-level sanitization may help reduce risk.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- Go
- Date Reserved
- 2026-04-28T00:21:12.791Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a1079f0e1370fbb48159db6
Added to database: 05/22/2026, 15:44:48 UTC
Last enriched: 06/29/2026, 22:48:18 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 89
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