XSS in Openwrt
CVE-2026-62948
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.
Vulnerability class: XSS (Cross-Site Scripting)
Published · last modified .
CVSS v3 metric
CVSS v3 base score 9.6 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.006 (46.6th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 46.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000
Affected products
- Openwrt — versions < 25.12.5
Weakness classification (CWE)
References
- github.com/openwrt/openwrt/security/advisories/GHSA-hhmc-92hw-535f (Exploit, Mitigation, Vendor Advisory)
- github.com/openwrt/odhcpd/pull/404 (Patch, Issue Tracking)
- github.com/openwrt/luci/commit/55379d04fcc3c605003a5001d6135cf02ae6048a (Patch)
- github.com/openwrt/odhcpd/commit/68f382690bfaec56d5b1f31c3c31c48bcb642e3a (Patch)
- github.com/openwrt/openwrt/releases/tag/v25.12.5 (Release Notes)
Frequently asked questions
- What is CVE-2026-62948?
- CVE-2026-62948 is a critical-severity vulnerability in Openwrt, classified under Cross-site Scripting. CVSS score: 9.6/10. Published 2026-07-15.
- How severe is CVE-2026-62948?
- Critical severity. CVSS v3 base score is 9.6 out of 10.