{"id":"CVE-2026-12503","state":"PUBLISHED","title":"Loytec LINX firmware: Improper Link Resolution in /usr/bin/larm_starter","description":"Improper Link Resolution (CWE-59) in `/usr/bin/larm_starter` in Loytec L-INX, L-GATE, L-ROC, L-IOB, L-DALI, L-VIS and L-PAD through 8.4.16 on LINX-A64 allows an authenticated `larmapp` attacker to make `/etc/passwd` writable by the `larmapp` group (leading to root privilege escalation) via a symlink attack on `/etc/lighttpd/ssl/server.pem`.","publishedAt":"2026-07-24T13:57:56.691Z","updatedAt":"2026-07-24T14:57:47.202Z","severity":{"score":9.2,"label":"Critical","version":"4.0","vector":"CVSS:4.0/AV:L/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:N/SI:H/SA:N","source":"NCSC.ch"},"assigner":"NCSC.ch","products":["Loytec LIP-ME20xC","Loytec L-INX","Loytec L-GATE","Loytec L-ROC","Loytec L-IOB","Loytec L-DALI","Loytec L-VIS","Loytec L-PAD"],"affected":[{"vendor":"Loytec","product":"LIP-ME20xC","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"8.4.16","versionType":"custom"}]},{"vendor":"Loytec","product":"L-INX","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"8.4.16","versionType":"custom"}]},{"vendor":"Loytec","product":"L-GATE","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"8.4.16","versionType":"custom"}]},{"vendor":"Loytec","product":"L-ROC","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"8.4.16","versionType":"custom"}]},{"vendor":"Loytec","product":"L-IOB","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"8.4.16","versionType":"custom"}]},{"vendor":"Loytec","product":"L-DALI","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"8.4.16","versionType":"custom"}]},{"vendor":"Loytec","product":"L-VIS","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"8.4.16","versionType":"custom"}]},{"vendor":"Loytec","product":"L-PAD","defaultStatus":"unaffected","versions":[{"version":"0","status":"affected","lessThanOrEqual":"8.4.16","versionType":"custom"}]}],"references":["https://www.loytec.com/support/product-security/advisories/8520-dibt-cve-20260526-0002-symlink-following-in-chown-chmod-critical"],"weaknesses":["CWE-59"],"ingestedAt":"2026-10-29T20:10:52.580Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/12xxx/CVE-2026-12503.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-12503","state":"PUBLISHED","datePublished":"2026-07-24T13:57:56.691Z","dateUpdated":"2026-07-24T14:57:47.202Z","assignerShortName":"NCSC.ch","assignerOrgId":"455daabc-a392-441d-aa46-37d35189897c","dateReserved":"2026-06-17T09:48:11.206Z"},"containers":{"cna":{"title":"Loytec 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