Openwrt: community verdicts

3 notable / known-exploited Openwrt CVEs the community has triaged.

ⓘ Not an exhaustive list: we focus on the findings that matter (exploited / notable). For every Openwrt CVE, see NVD ↗.

CVE-2026-55490MED 6.5EPSS 1%
OpenWrt is a Linux operating system targeting embedded devices. Before v25.12.5, an integer underflow in handle_send_a() of the Emergency Access Daemon allows any unauthenticated attacker on the local network to crash the daemon by sending a single crafted UDP packet. The message length underflows before a bounds check and is then passed to memcpy as a very large size. This issue is fixed v25.12.5.
CVE-2021-27821MED 6.1EPSS 1%
The Web Interface for OpenWRT LuCI version 19.07 and lower has been discovered to have a cross-site scripting vulnerability.
CVE-2021-33425MED 5.4EPSS 1%
A stored cross-site scripting (XSS) vulnerability was discovered in the Web Interface for OpenWRT LuCI version 19.07 which allows attackers to inject arbitrary Javascript in the OpenWRT Hostname via the Hostname Change operation.