CVE-2026-121544 PUBLISHED

Koodo Reader through 2.4.6 Path Traversal via OPDS Cover and Download Handlers

Assigner: VulnCheck
Reserved: 03.11.2026 Published: 03.11.2026 Updated: 03.11.2026

Koodo Reader through 2.4.6 contains a path traversal vulnerability in the self-hosted HTTP server's OPDS handlers that allows authenticated attackers to read files outside the upload directory. Attackers can upload a crafted books.db with a cover value containing ../ sequences, then request /opds/cover/{key} to read files accessible to the server process.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N
CVSS Score: 6.9

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	None	Integrity	None
Attack Requirements	None	Availability	None	Availability	None
Privileges Required	High
User Interaction	None

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N
CVSS Score: 4.9

Attack Vector	Network	Scope	Unchanged
Attack Complexity	Low	Confidentiality Impact	High
Privileges Required	High	Integrity Impact	None
User Interaction	None	Availability Impact	None

CVSS 3.1

Product Status

Vendor	koodo-reader
Product	koodo-reader
Versions	Default: unaffected affected from 0 to 2.4.6 (incl.)

Credits

George Chen finder

References

Problem Types

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') CWE