CVE-2026-62948 Cross-site scripting in openwrt

Critical 9.6 Published 15 Jul 2026 Updated 15 Jul 2026

Unauthenticated DHCPv6 clients can inject malicious HTML into lease files, leading to stored XSS in the LuCI admin interface.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: A user has to click or open something
Fix: None listed

What is CVE-2026-62948?

CVE-2026-62948 is a critical cross-site scripting vulnerability in Openwrt Openwrt, published on 15 Jul 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.

Official 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.

Weakness: CWE-79, CWE-150, CWE-117

Which versions are affected by CVE-2026-62948?

It affects 1 product.

Products include Openwrt Openwrt.

How do I fix CVE-2026-62948?

No fix has been published for CVE-2026-62948 yet. Limit exposure of the affected software until one is available.

Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.

Is CVE-2026-62948 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-62948 exists.

All Openwrt Openwrt vulnerabilities

Sources

Also known as GHSA-hhmc-92hw-535f.