Openwrt before v21.02.3 and Openwrt v22.03.0-rc6 were discovered to contain two skip loops in the function header_value(). This vulnerability allows attackers to access sensitive information via a crafted HTTP request.

There is missing input validation of host names displayed in OpenWrt before 19.07.8. The Connection Status page of the luci web-interface allows XSS, which can be used to gain full control over the affected system via ICMP.

In OpenWrt 19.07.x before 19.07.7, when IPv6 is used, a routing loop can occur that generates excessive network traffic between an affected device and its upstream ISP's router. This occurs when a link prefix route points to a point-to-point link, a destination IPv6 address belongs to the prefix and is not a local IPv6 address, and a router advertisement is received with at least one global unique IPv6 prefix for which the on-link flag is set. This affects the netifd and odhcp6c packages.

libuci in OpenWrt before 18.06.9 and 19.x before 19.07.5 may encounter a use after free when using malicious package names. This is related to uci_parse_package in file.c and uci_strdup in util.c.

libubox in OpenWrt before 18.06.7 and 19.x before 19.07.1 has a tagged binary data JSON serialization vulnerability that may cause a stack based buffer overflow.

uhttpd in OpenWrt through 18.06.5 and 19.x through 19.07.0-rc2 has an integer signedness error. This leads to out-of-bounds access to a heap buffer and a subsequent crash. It can be triggered with an HTTP POST request to a CGI script, specifying both "Transfer-Encoding: chunked" and a large negative Content-Length value.