{"schemaVersion":3,"id":"CVE-2026-55159","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"luci-app-adblock-fast a WebUI for fast, lightweight DNS-based ad-blocker for OpenWrt that works with dnsmasq, smartdns, or unbound. Prior to 1.2.4-2, the luci.adblock-fast.setCronEntry RPC method accepts an entry argument containing carriage-return or line-feed characters and serializes it into /etc/crontabs/root as though it were one logical line. An authenticated delegated user with the luci-app-adblock-fast write ACL can therefore create an additional physical root cron entry through applications/luci-app-adblock-fast/root/usr/share/rpcd/ucode/luci.adblock-fast, resulting in persistent command execution as UID 0 when cron runs. The issue is not demonstrated for unauthenticated callers or users without the component write ACL. This vulnerability is fixed in 1.2.4-2.","dates":{"published":"2026-09-21T19:24:03.581Z","modified":"2026-09-29T14:01:11.023Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":8.8,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":8.8,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":8.8,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.0049,"percentile":0.40897,"severity":"low","asOf":"2026-10-20T00:00:00.000Z","change":{"pp":null,"baselineDate":null,"baselineScore":null},"history":[{"date":"2026-09-22T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00954,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00954,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.0049,"percentile":0.40897}],"last30":[{"date":"2026-09-22T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00954,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00954,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.0049,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.0049,"percentile":0.40897}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-93","name":"Improper Neutralization of CRLF Sequences ('CRLF Injection')","description":"The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs.","type":"weakness","status":"Draft","abstraction":"Base","likelihoodOfExploit":null,"url":"https://cwe.mitre.org/data/definitions/93.html"}],"affected":[{"vendor":"openwrt","product":"luci-app-adblock-fast","name":"luci-app-adblock-fast","label":"luci-app-adblock-fast","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 1.2.4-2","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 1.2.4-2","eol":null,"hubHref":"/vendor/openwrt/luci-app-adblock-fast"}],"affectedCount":1,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://github.com/openwrt/luci/security/advisories/GHSA-ggpf-xrph-wg5v","label":"github.com/openwrt/luci/security/advisories/GHSA-ggpf-xrph-wg5v","hostname":"github.com","tags":["X Refsource CONFIRM"]},{"url":"https://github.com/openwrt/luci/pull/8705","label":"github.com/openwrt/luci/pull/8705","hostname":"github.com","tags":["X Refsource MISC"]},{"url":"https://github.com/openwrt/luci/commit/9ccd99b5898457e5ef39dc21aea226d7fb6e5c7e","label":"github.com/openwrt/luci/commit/9ccd99b5898457e5ef39dc21aea226d7fb6e5c7e","hostname":"github.com","tags":["X Refsource MISC"]},{"url":"https://github.com/openwrt/luci/commit/f67461fd0255bf992b2b559c22ec288067f2f9da","label":"github.com/openwrt/luci/commit/f67461fd0255bf992b2b559c22ec288067f2f9da","hostname":"github.com","tags":["X Refsource MISC"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2026-09-21T19:24:03.581Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-09-29T14:01:11.023Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":35,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-21T11:32:54.720Z","stale":false,"partial":false}}