جزئیات آسیب‌پذیری

MikroTik RouterOS before 7.25beta4 contains an improper input validation vulnerability in the labelled-VPN NLRI iterators of the routing service that allows an unauthenticated on-path attacker to crash the BGP service by sending a malformed MP_REACH_NLRI UPDATE message with a prefix-length value below the minimum valid for a labelled-VPN NLRI, which passes validation while describing a route with a negative-length address portion. Attackers can repeatedly send a single BGP UPDATE packet carrying a VPNv4 or VPNv6 NLRI with an out-of-bounds prefix-length to indefinitely hold down the BGP plane, causing session termination without a NOTIFICATION and triggering a service malfunction on the device. The fix is carried only in 7.25beta4, a development build; the current stable release 7.24.2 and the current long-term release 7.23.5 both remain affected.

• https://forum.mikrotik.com/t/7-25beta-development-is-released/272788 release-notespatch
• https://www.vulncheck.com/advisories/mikrotik-routeros-improper-input-validation-dos-via-bgp-labelled-vpn-nlri third-party-advisory