DNS: DNSmasq answer_auth and answer_request Integer Underflow
An integer underflow vulnerability has been reported in dnsmasq. A remote, unauthenticated attacker can exploit this vulnerability by sending a large UDP packet to the target system. Successful exploitation results in termination of the dnsmasq process.
Extended Description
In dnsmasq before 2.78, if the DNS packet size does not match the expected size, the size parameter in a memset call gets a negative value. As it is an unsigned value, memset ends up writing up to 0xffffffff zero's (0xffffffffffffffff in 64 bit platforms), making dnsmasq crash.
Affected Products
Thekelleys dnsmasq
Short Name
DNS:REQUEST:DNS-INT-UNDERFLOW
Severity
Minor
Recommended
True
Recommended Action
Drop
Category
DNS
Keywords
CVE-2017-13704 DNSmasq Integer Underflow and answer_auth answer_request bid:101085
Release Date
10/24/2017
Supported Platforms
srx-branch-12.3
srx-19.3
srx-branch-19.3
vsrx3bsd-19.2
srx-branch-19.4
vsrx-19.4
mx-12.3
mx-19.4
vmx-19.4
mx-19.3
vsrx3bsd-19.4
srx-19.4
vsrx-12.3
vmx-19.3
vsrx-19.2
srx-12.3
Sigpack Version
3590
False Positive
Unknown
Vendors
Redhat
Fedoraproject
Thekelleys
Novell
Debian
Canonical
CVSS Score
5.0