Description
OpenWrt is a Linux operating system targeting embedded devices. Prior to 25.12.5, odhcpd writes a DHCPv6 client FQDN option 39 hostname into /tmp/odhcpd.leases through src/statefiles.c statefiles_write_state6() and statefiles_write_state4() without escaping, allowing newline injection of forged lease lines that LuCI rpcd-mod-luci getDHCPLeases displays through htdocs/luci-static/resources/view/status/include/40_dhcp.js and htdocs/luci-static/resources/luci.js dom.append as live HTML in the Active DHCPv6 Leases admin page. This vulnerability is fixed in 25.12.5.
Affected products
openwrt: openwrt
References6
- github.com/openwrt/openwrt/security/advisories/GHSA-hhmc-92hw-5… ExploitMitigationVendor Advisory
- github.com/openwrt/openwrt/security/advisories/GHSA-hhmc-92hw-5… ExploitMitigationVendor Advisory
- github.com/openwrt/luci/commit/55379d04fcc3c605003a5001d6135cf0… Patch
- github.com/openwrt/odhcpd/commit/68f382690bfaec56d5b1f31c3c31c4… Patch
- github.com/openwrt/odhcpd/pull/404 Issue TrackingPatch
- github.com/openwrt/openwrt/releases/tag/v25.12.5 Release Notes
Metrics
- CVSS 3.1
-
9.6
CRITICAL
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H - EPSS — exploit probability
- 1% percentile: 48 · as of 15 November 2026
- CWE
- CWE-79CWE-117CWE-150
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