Is CVE-2026-112951 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-112951 being exploited in the wild.

How severe is CVE-2026-112951?

Medium severity, with a CVSS score of 5.4, published 20 October 2026.

Which products and versions are affected?

ApostropheCMS Apostrophe before 4.34.0; apostrophe (npm) < 4.34.0, SEMVER:introduced=0,fixed=4.34.0.

Is there a fix for CVE-2026-112951?

Yes. apostrophe (npm): upgrade to 4.34.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-112951 attacked?

It is attacked over the network, in a web application.

Am I affected by CVE-2026-112951?

Check whether you run ApostropheCMS Apostrophe or apostrophe (npm) 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-2026-112951: ApostropheCMS color field stored XSS via TinyColor bypass

Q: Is there a fix for CVE-2026-112951?

Yes. apostrophe (npm): upgrade to 4.34.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-112951 attacked?

It is attacked over the network, in a web application.

Q: Am I affected by CVE-2026-112951?

Check whether you run ApostropheCMS Apostrophe or apostrophe (npm) 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-2026-112951 · Severity: medium · CVSS 5.4 · Published 2026-10-20

ApostropheCMS is an open-source Node.js content management system used to build and manage websites. The color field accepts arbitrary HTML when appended after a valid color prefix, allowing authenticated editors to inject malicious scripts that execute when the page is viewed. This stored cross-site scripting (XSS) can lead to session hijacking, data theft, or defacement.

Technologies: ApostropheCMS Apostrophe, apostrophe (npm). Vendors: ApostropheCMS, npm.

Quick answers

Is CVE-2026-112951 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-112951 being exploited in the wild.
How severe is CVE-2026-112951?: Medium severity, with a CVSS score of 5.4, published 20 October 2026.
Which products and versions are affected?: ApostropheCMS Apostrophe before 4.34.0; apostrophe (npm) < 4.34.0, SEMVER:introduced=0,fixed=4.34.0.
Is there a fix for CVE-2026-112951?: Yes. apostrophe (npm): upgrade to 4.34.0 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-112951 attacked?: It is attacked over the network, in a web application.
Am I affected by CVE-2026-112951?: Check whether you run ApostropheCMS Apostrophe or apostrophe (npm) 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

apostrophe (npm): upgrade to 4.34.0 or later
```
npm install apostrophe@4.34.0
```

Technical details

The color field validation in ApostropheCMS uses TinyColor but does not enforce that the entire value matches a valid color format, allowing trailing HTML to be stored. An authenticated user with edit rights can bypass validation by prefixing arbitrary HTML with a valid rgb() or hsl() value (e.g., "rgb(0,0,0)<script>alert('xss')</script>"). When the stored value is rendered on the front end, the payload executes in the context of the page.

Affected products

ApostropheCMS Apostrophe before 4.34.0

Identifiers

CVE-2026-112951
GHSA-vmgj-9cwm-cf3h

Timeline

2026-10-20: disclosed

References

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