{"id":"CVE-2026-55159","published":"2026-09-21T20:17:26.500","lastModified":"2026-09-24T21:25:27.050","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.","cvssScore":8.8,"cvssSeverity":"HIGH","cvssVector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H","cwes":["CWE-93"],"vendors":[],"products":[],"references":[{"url":"https://github.com/openwrt/luci/commit/9ccd99b5898457e5ef39dc21aea226d7fb6e5c7e","tags":[]},{"url":"https://github.com/openwrt/luci/commit/f67461fd0255bf992b2b559c22ec288067f2f9da","tags":[]},{"url":"https://github.com/openwrt/luci/pull/8705","tags":[]},{"url":"https://github.com/openwrt/luci/security/advisories/GHSA-ggpf-xrph-wg5v","tags":[]}],"exploitRefs":[{"url":"https://github.com/openwrt/luci/commit/9ccd99b5898457e5ef39dc21aea226d7fb6e5c7e","tags":[]},{"url":"https://github.com/openwrt/luci/commit/f67461fd0255bf992b2b559c22ec288067f2f9da","tags":[]},{"url":"https://github.com/openwrt/luci/pull/8705","tags":[]},{"url":"https://github.com/openwrt/luci/security/advisories/GHSA-ggpf-xrph-wg5v","tags":[]}],"hasPoc":true,"ai":{"summary":"The flaw allows an authenticated delegated user to inject malicious cron entries, leading to persistent command execution as root.","exploitability":"Exploitation requires authentication and access to the luci-app-adblock-fast write ACL. The vulnerability is not demonstrated for unauthenticated callers.","blast_radius":"If exploited, the impact is severe, as it allows for persistent root-level command execution.","remediation":"Upgrade to version 1.2.4-2 or later.","detection":"No reliable host or network indicator is derivable from the published description.","tags":["rce","auth-bypass","web","cron","openwrt"],"model":"qwen2.5:7b-instruct","analyzedAt":"2026-09-29T09:15:58.278Z"}}