CVE-2026-121550

nnn through 5.3 contains an insecure file handling vulnerability that allows local attackers to redirect writes because main() accepts an existing NNN_FIFO path without verifying it is a FIFO. Attackers can pre-create the documented predictable /tmp/nnn.fifo path as a symlink or readable regular file, causing victim-writable files to be overwritten or leaking the victim's browsed paths.

CVSS v3 3.3 LOW

3.3^/10

CVSS v3 : LOW

Vector :

Exploitability : 0.8 / Impact : 2.5

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/jarun/nnn
https://github.com/jarun/nnn/blob/v5.3/src/nnn.c#L10635
https://github.com/jarun/nnn/blob/v5.3/src/nnn.c#L7433
https://github.com/jarun/nnn/commit/04715921aece0257fef7a8558c0783493d98efff
https://github.com/jarun/nnn/issues/2188
https://www.vulncheck.com/advisories/nnn-through-5.3-symlink-following-write-via-nnn-fifo-handling

Configurations

No configuration.

History

03 Nov 2026, 16:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-11-03 16:17

Updated : 2026-11-03 16:30

NVD link : CVE-2026-121550

Mitre link : CVE-2026-121550

CVE.ORG link : CVE-2026-121550

JSON object : View

Products Affected

No product.

CWE

CWE-59

Improper Link Resolution Before File Access ('Link Following')

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