SB2020031626 - Buffer overflow in OpenWrt

Description

This security bulletin contains information about 1 vulnerability.

1) Buffer overflow (CVE-ID: CVE-2019-19945)

CWE-ID: CWE-119 - Memory corruption

CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

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.

Remediation

Install update from vendor's website.

References

• https://github.com/openwrt/openwrt/commits/master
• https://openwrt.org/advisory/2020-01-13-1