SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityDeferred

CVE-2025-64486

In versions 8.13.0 and prior, calibre does not validate filenames when handling binary assets in FB2 files, allowing an attacker to write arbitrary files on the filesystem when viewing or converting a malicious FictionBook file.

CRITICAL 9.3EPSS 0.18%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.18%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

calibre is an e-book manager. In versions 8.13.0 and prior, calibre does not validate filenames when handling binary assets in FB2 files, allowing an attacker to write arbitrary files on the filesystem when viewing or converting a malicious FictionBook file. This can be leveraged to achieve arbitrary code execution. This issue is fixed in version 8.14.0.

CVSS 4.0
9.3 CRITICALCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/M
EPSS
0.18% probability · 8th percentile
CISA KEV
Not listed
Weakness
CWE-73
Source
security-advisories@github.com

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.