CVE-2026-42150: wlc: print_html outputs API data without HTML escaping, enabling stored XSS

Severity: medium (CVSS 4.8 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-05-08 · updated 2026-10-26
Weakness: CWE-79

Description

wlc is a Weblate command-line client using Weblate's REST API. Prior to version 2.0.0, the HTML output format in wlc embeds API response data into HTML without escaping, allowing cross-site scripting when the output is rendered in a browser. This issue has been patched in version 2.0.0.

Affected products

WeblateOrg wlc: before 2.0.0 — fixed in 2.0.0

How to fix

Upgrade to a fixed version: WeblateOrg wlc 2.0.0. Check the vendor advisory for mitigations.

References

https://github.com/WeblateOrg/wlc/commit/0f3e58f6d7457b05d48ef40f579a172c4c8b8469
https://github.com/WeblateOrg/wlc/pull/1327
https://github.com/WeblateOrg/wlc/releases/tag/2.0.0
https://github.com/WeblateOrg/wlc/security/advisories/GHSA-gx2m-mcc2-r4p3

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