{"affected":[{"defaultStatus":"unaffected","product":"nnn","source":"CNA: VulnCheck","vendor":"jarun","versions":[{"lessThanOrEqual":"5.3","status":"affected","version":"0","versionType":"custom"}]}],"cveId":"CVE-2026-121550","cwes":["CWE-59"],"description":"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.","epss":{"date":"2026-11-09","percentile":0.01619,"score":0.00116},"exploits":[],"kev":null,"metrics":[{"score":1,"severity":"low","source":"CNA: VulnCheck","vector":"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","version":"4.0"},{"score":3.3,"severity":"low","source":"CNA: VulnCheck","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N","version":"3.1"},{"score":1,"severity":"low","source":"NVD: disclosure@vulncheck.com","vector":"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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","version":"4.0"},{"score":3.3,"severity":"low","source":"NVD: disclosure@vulncheck.com","vector":"CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:N","version":"3.1"}],"modifiedAt":1794236976936,"publishedAt":1793719029442,"references":[{"source":"CNA: VulnCheck","tags":["issue-tracking"],"url":"https://github.com/jarun/nnn/issues/2188"},{"source":"CNA: VulnCheck","tags":["product"],"url":"https://github.com/jarun/nnn"},{"source":"CNA: VulnCheck","tags":["patch"],"url":"https://github.com/jarun/nnn/commit/04715921aece0257fef7a8558c0783493d98efff"},{"source":"CNA: VulnCheck","tags":["technical-description"],"url":"https://github.com/jarun/nnn/blob/v5.3/src/nnn.c#L10635"},{"source":"CNA: VulnCheck","tags":["technical-description"],"url":"https://github.com/jarun/nnn/blob/v5.3/src/nnn.c#L7433"},{"source":"CNA: VulnCheck","tags":["third-party-advisory"],"url":"https://www.vulncheck.com/advisories/nnn-through-5.3-symlink-following-write-via-nnn-fifo-handling"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/jarun/nnn"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/jarun/nnn/blob/v5.3/src/nnn.c#L10635"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/jarun/nnn/blob/v5.3/src/nnn.c#L7433"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/jarun/nnn/commit/04715921aece0257fef7a8558c0783493d98efff"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://github.com/jarun/nnn/issues/2188"},{"source":"disclosure@vulncheck.com","tags":[],"url":"https://www.vulncheck.com/advisories/nnn-through-5.3-symlink-following-write-via-nnn-fifo-handling"}],"remediation":[{"kind":"fix","source":"CNA: VulnCheck","text":"The reporting source identifies this reference as a patch. Check the advisory for affected versions and supported release branches.","url":"https://github.com/jarun/nnn/commit/04715921aece0257fef7a8558c0783493d98efff"}],"revision":"3321ca89d226cdd5566eb20a770179ba1488b571e40e85240471327c6c776c47","sources":[{"modifiedAt":1794236976936,"name":"CNA: VulnCheck","retrievedAt":1794240569617,"url":"https://www.cve.org/CVERecord?id=CVE-2026-121550"},{"modifiedAt":1793723417150,"name":"NVD","retrievedAt":1793730103490,"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-121550"},{"modifiedAt":null,"name":"FIRST EPSS","retrievedAt":1794240591030,"url":"https://api.first.org/data/v1/epss?cve=CVE-2026-121550"}],"ssvc":{"assessedAt":1794236966877,"automatable":"no","exploitation":"none","source":"ADP: CISA-ADP","technicalImpact":"partial"},"status":"published","title":"nnn through 5.3 Symlink-Following Write via NNN_FIFO Handling","updatedAt":1794240591030}