nnn through 5.3 Insecure Temporary File Symlink Overwrite via pdfread and nuke Plugins
Written by anthropic/claude-haiku-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- Fix or patch referenced
- Who is exposed
- Not reported
Do first: Apply the patch listed under Evidence.
- Exploitation?/40Exploitation: unknown (data gap). No CISA SSVC exploitation rating yet
- Exposure?/25Exposure: unknown (data gap). No advisory context yet
- Reach?/20Reach: unknown (data gap). No tracked technology or package matched
- Severity4.1/10CVSS 4.1
- No patch0/5No signal
What would change the score
- Would score about 59 if added to CISA KEV
- Would score about 54 if CISA's SSVC rates exploitation active
- Would score about 26 if advisories confirm default setups are exposed
CVE-2026-121549 is not in CISA's Known Exploited Vulnerabilities (KEV) catalog. No public exploit code is tracked. It is rated CVSS 4.1 (medium) and affects nnn; a fix or patch is referenced.
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- Published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 4/100 · provisional
- Fix
- Fix or patch referenced
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
Summary
The nnn file manager (up to and including version 5.3) is affected, specifically its pdfread and nuke plugins. A local attacker could exploit predictable temporary file paths to trick these plugins into overwriting arbitrary files that the user has permission to write, potentially destroying or corrupting data.
Read the original description
nnn through 5.3 contains an insecure temporary file vulnerability in the pdfread and nuke plugins that allows local attackers to overwrite files by exploiting predictable paths in /tmp. Attackers can pre-create a symlink at the name-derived or PID-derived path so the victim's plugin truncates and overwrites any file the victim can write.
What to do
Apply the patch listed under Evidence.
Timeline
- CVE published
- First seen by cve.now
Affected versions
- jarun nnn
through 5.3
Evidence 6
- Patch
- Report
- Repository
- Repository
- Repository
- Link
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-121549
Is CVE-2026-121549 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
Which versions are affected by CVE-2026-121549?
nnn: through 5.3.Source: cve.now feed data