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CVE-2026-39826 (GCVE-0-2026-39826)

Vulnerability from cvelistv5 – Published: 2026-05-07 19:41 – Updated: 2026-05-08 14:05
VLAI
Title
Escaper bypass leads to XSS in html/template
Summary
If a trusted template author were to write a <script> tag containing an empty 'type' attribute or a 'type' attribute with an ASCII whitespace, the execution of the template would incorrectly escape any data passed into the <script> block.
Severity
6.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-05-08 14:04 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Assigner
References
Impacted products
Vendor Product Version CPE status
Go standard library html/template Affected: 0 , < 1.25.10 (semver)
Affected: 1.26.0-0 , < 1.26.3 (semver)
guessed Create a notification for this product.
Credits
Mundur (https://github.com/M0nd0R)
Show details on NVD website
To clipboard 

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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