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CVE-2026-121550

1.0 lowEPSS 0.1%

Low (1.0). EPSS 0.1% estimated probability of exploitation activity in the next 30 days.

On this page
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.

Severity

CVSS 4.0

1.0 low
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:A/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N

CVSS 3.1

3.3 low
CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N
EPSS
0.1% estimated probability of exploitation activity in the next 30 days; 2nd percentile. Scored 2026-11-04. A forecast for this CVE across the internet, not for your own systems.
CWE
CWE-59 Improper Link Resolution Before File Access (Link Following)
OWASP Top 10
A01:2025 Broken Access Control
Published
Modified
Record from
the NVD, synced

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Versions

From the CNA's record in the CVE List.

ProductAffected
jarun nnnthrough 5.3

Attack patterns (CAPEC)

  • CAPEC-17 Using Malicious Files Likelihood: High · Severity: Very High
  • CAPEC-35 Leverage Executable Code in Non-Executable Files Likelihood: High · Severity: Very High
  • CAPEC-76 Manipulating Web Input to File System Calls Likelihood: High · Severity: Very High
  • CAPEC-132 Symlink Attack Likelihood: Low · Severity: High

The attack patterns MITRE's CAPEC relates to this record's weaknesses, as MITRE names them. Credits.

References

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