CVE-2026-62948
CRITICALOpenWrt odhcpd/LuCI: unauthenticated DHCPv6 client can inject lease-file lines via FQDN hostname → stored XSS in the LuCI admin UI
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.
Detection & mitigation playbook
VulnerabilityDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for the affected component. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Remediation status
No patched version of the affected component has shipped for CVE-2026-62948 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2026-62948 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-62948. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-62948 in your dependencies?
O3 detects CVE-2026-62948 across dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.