DNS: Multiple Vendors DNS NSEC3 Response Handling Denial Of Service
This signature detects attempts to exploit a known vulnerability against Multiple Vendors DNS NSEC3 Response Handling. A successful attack can result in a denial-of-service condition.
Extended Description
The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance is skipped) allows remote attackers to cause a denial of service (CPU consumption for SHA-1 computations) via DNSSEC responses in a random subdomain attack, aka the "NSEC3" issue. The RFC 5155 specification implies that an algorithm must perform thousands of iterations of a hash function in certain situations.
References
CVE: CVE-2023-50868
mx-19.3
vmx-19.3
vsrx-19.2
srx-19.3
srx-branch-19.3
vsrx3bsd-19.2
srx-19.4
vsrx3bsd-19.4
srx-branch-19.4
vsrx-19.4
vmx-19.4
mx-19.4
srxevo-25.4
vsrx-26.2
srx-26.2
srx-branch-26.2
vsrx3bsd-26.2
mx-12.3
srx-12.3
srx-branch-12.3
vsrx-12.3