HOMEVULNERABILITIESCVE-2026-26065
HIGHPOC

CVE-2026-26065

CWE-22Published: February 20, 2026· Updated: Feb 20, 2026

8.8
CVSS v3.1
EPSS:0.03%probability of exploitation in 30 daysPercentile:8.4th

Official Description

calibre is a cross-platform e-book manager for viewing, converting, editing, and cataloging e-books. Versions 9.2.1 and below are vulnerable to Path Traversal through PDB readers (both 132-byte and 202-byte header variants) that allow arbitrary file writes with arbitrary extension and arbitrary content anywhere the user has write permissions. Files are written in 'wb' mode, silently overwriting existing files. This can lead to potential code execution and Denial of Service through file corruption. This issue has been fixed in version 9.3.0.

NVD Source

Technical Analysis

CVE-2026-26065 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 8.8.

A proof-of-concept (PoC) exploit exists for CVE-2026-26065. While not yet confirmed in active campaigns, the availability of PoC code increases exploitation risk substantially.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Vendors & Products

calibre-ebook1 product
calibre
Source: NVD CPE · 1 total CPE entries

Exploit & PoC Resources

POC AVAILABLEProof-of-concept code exists
External links open in a new tab. Always verify in a controlled environment before use.

Official Patches & Advisories

All References (2)

Quick Facts

CVE IDCVE-2026-26065
CVSS Score8.8 / 10
SeverityHIGH
WeaknessCWE-22
CISA KEVNo
ExploitPOC
EPSS (30d)0.03%
Affected1 vendor
PublishedFeb 20, 2026

Related CVEs (CWE-22)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2026-26065 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.