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PatchSiren cyber security CVE debrief

CVE-2026-45011 apostrophecms CVE debrief

ApostropheCMS version 4.29.0 has a stored cross-site scripting vulnerability in the image widget functionality. A user with the Editor role can configure an image widget link to use a javascript: URL payload. Because editors have permission to publish pages, the malicious widget can be published to the live site. When another user, including an administrator or public visitor, clicks the affected image/link, arbitrary JavaScript executes in the victim’s browser. As of time of publication, no known patched versions are available.

Vendor
apostrophecms
Product
apostrophe
CVSS
HIGH 7.3
CISA KEV
Not listed in stored evidence
Original CVE published
2026-06-12
Original CVE updated
2026-06-15
Advisory published
2026-06-12
Advisory updated
2026-06-15

Who should care

Users of ApostropheCMS version 4.29.0, particularly those with Editor roles, should be aware of this vulnerability and take necessary precautions.

Technical summary

The vulnerability is caused by the lack of proper input validation in the image widget functionality of ApostropheCMS version 4.29.0. An attacker with Editor privileges can inject malicious JavaScript code into the image widget link, which can then be executed by other users who click on the affected image or link.

Defensive priority

HIGH

Recommended defensive actions

  • Users of ApostropheCMS version 4.29.0 should update to a patched version as soon as it becomes available.
  • In the meantime, users can take steps to mitigate the vulnerability by limiting Editor privileges or closely monitoring image widget configurations.

Evidence notes

The CVE record for CVE-2026-45011 provides additional information on the vulnerability, including its CVSS score and vector.

Sources and references

Verified primary and authoritative sources

  • CVE-2026-45011 CVE Program record

    Publisher, destination, and source semantics verified

    URL: https://www.cve.org/CVERecord?id=CVE-2026-45011

    CVE Program - Official CVE Program record with source-provided CVE metadata.

  • CVE-2026-45011 NVD vulnerability detail

    Publisher, destination, and source semantics verified

    URL: https://nvd.nist.gov/vuln/detail/CVE-2026-45011

    NIST National Vulnerability Database - Official NIST NVD detail page and source-specific vulnerability assessment.

Supplemental references

Methodology and review provenance

AI-assisted synthesis based on stored public vulnerability evidence. System validation, approval state, and publication status do not by themselves establish human review of this revision. PatchSiren helps prioritize defensive review and does not prove exposure or remediation on any system.