CVE-2026-54002
Stored XSS in Kirby CMS via DOM sanitization bypass.
Is CVE-2026-54002 being exploited?
Not confirmed. CVE-2026-54002 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.55% probability of exploitation in the next 30 days.
How severe is CVE-2026-54002?
CVE-2026-54002 is rated High. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-54002?
Yes. A fix has been recorded for CVE-2026-54002. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-54002 affect?
CVE-2026-54002 affects Kirby CMS < 4.9.4, Kirby CMS < 5.4.4, Plugins using writer/list fields or Dom::sanitize()/Sane::sanitize() family. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-54002?
Upgrade to Kirby 4.9.4 or 5.4.4; audit and harden input sanitization and plugins.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Stored cross-site scripting: attackers can inject malicious scripts via writer/list fields or sanitize calls to steal sessions, escalate access, or deface sites.
Immediate action required
- affected< 4.9.4
- affected>= 5.0.0 and < 5.4.4
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.