CVE-2026-26064
Path traversal in calibre <=9.2.1 enables arbitrary file writes; Windows RCE via Startup folder.
Is CVE-2026-26064 being exploited?
Not confirmed. CVE-2026-26064 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 0.88% probability of exploitation in the next 30 days.
How severe is CVE-2026-26064?
CVE-2026-26064 is rated Critical with a CVSS score of 9.3. 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-2026-26064?
Yes. A fix has been recorded for CVE-2026-26064. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-26064 affect?
CVE-2026-26064 affects calibre <= 9.2.1. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-26064?
Upgrade to 9.3.0+
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
RCE on Windows by writing a payload to the Startup folder; arbitrary file writes via path traversal.
Patch when possible
- affected< 9.3.0
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.