Is CVE-2026-42150 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-42150 being exploited in the wild.

How severe is CVE-2026-42150?

Medium severity, with a CVSS score of 5.1, published 8 May 2026.

Which products and versions are affected?

wlc (PyPI) < 2.0.0, ECOSYSTEM:introduced=0,fixed=2.0.0.

Is there a fix for CVE-2026-42150?

Yes. wlc (PyPI): upgrade to 2.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-42150 attacked?

It is attacked over the network, in a software library.

Am I affected by CVE-2026-42150?

Check whether you run wlc (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-42150: Weblate wlc cross-site scripting in HTML output format

Q: Which products and versions are affected?

wlc (PyPI) < 2.0.0, ECOSYSTEM:introduced=0,fixed=2.0.0.

Q: Is there a fix for CVE-2026-42150?

Yes. wlc (PyPI): upgrade to 2.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-42150 attacked?

It is attacked over the network, in a software library.

Q: Am I affected by CVE-2026-42150?

Check whether you run wlc (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-42150 · Severity: medium · CVSS 5.1 · Published 2026-05-08

wlc is a command-line tool used to interact with the Weblate translation platform. A security flaw in versions prior to 2.0.0 allows malicious data from the Weblate API to be converted into web-ready HTML without proper safety checks. If a user generates an HTML report and views it in a web browser, an attacker could execute malicious scripts, potentially leading to unauthorized actions or data theft within that browser session.

Technologies: wlc (PyPI). Vendors: PyPI.

Quick answers

Is CVE-2026-42150 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-42150 being exploited in the wild.
How severe is CVE-2026-42150?: Medium severity, with a CVSS score of 5.1, published 8 May 2026.
Which products and versions are affected?: wlc (PyPI) < 2.0.0, ECOSYSTEM:introduced=0,fixed=2.0.0.
Is there a fix for CVE-2026-42150?: Yes. wlc (PyPI): upgrade to 2.0.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-42150 attacked?: It is attacked over the network, in a software library.
Am I affected by CVE-2026-42150?: Check whether you run wlc (PyPI) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

wlc (PyPI): upgrade to 2.0.0 or later
```
pip install "wlc>=2.0.0"
```

Technical details

The wlc command-line client (prior to version 2.0.0) contains a stored cross-site scripting (XSS) vulnerability in its HTML output module. The `print_html` function embeds data retrieved from the Weblate REST API directly into HTML tags (such as <th> and <td>) without performing proper character escaping. An attacker with high privileges on a Weblate instance could inject malicious scripts into translation strings or metadata. When a user runs wlc with the `--format=html` flag and opens the resulting file in a browser, the script executes in the context of the local file or the domain hosting the report. This issue is addressed in version 2.0.0 by implementing a `format_html_value` helper to sanitize output.

Affected products

WeblateOrg wlc < 2.0.0

Identifiers

CVE-2026-42150
GHSA-gx2m-mcc2-r4p3
PYSEC-2026-2321

Timeline

2026-04-20: patched: Fix merged into main branch via PR #1327
2026-04-21: advisory: Vendor security advisory GHSA-gx2m-mcc2-r4p3 published
2026-05-08: disclosed: CVE-2026-42150 published to NVD

References

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