CVE-2017-13704

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.

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.

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.

CVE-2017-13704: Dnsmasq could be made to crash on a large DNS query. A DNS query received by UDP which exceeds 512 bytes (or the EDNS0 packet size, if different.) is enough to cause SIGSEGV.

CVE-2017-14491: A heap buffer overflow was found in dnsmasq in the code responsible for building DNS replies. An attacker could send crafted DNS packets to dnsmasq which would cause it to crash or, potentially, execute arbitrary code.

CVE-2017-14492: A heap buffer overflow was discovered in dnsmasq in the IPv6 router advertisement (RA) handling code. An attacker on the local network segment could send crafted RAs to dnsmasq which would cause it to crash or, potentially, execute arbitrary code. This issue only affected configurations using one of these options: enable-ra, ra-only, slaac, ra-names, ra-advrouter, or ra-stateless.

CVE-2017-14493: A stack buffer overflow was found in dnsmasq in the DHCPv6 code. An attacker on the local network could send a crafted DHCPv6 request to dnsmasq which would cause it to a crash or, potentially, execute arbitrary code.

CVE-2017-14494: An information leak was found in dnsmasq in the DHCPv6 relay code. An attacker on the local network could send crafted DHCPv6 packets to dnsmasq causing it to forward the contents of process memory, potentially leaking sensitive data.

CVE-2017-14495: A memory exhaustion flaw was found in dnsmasq in the EDNS0 code. An attacker could send crafted DNS packets which would trigger memory allocations which would never be freed, leading to unbounded memory consumption and eventually a crash. This issue only affected configurations using one of the options: add-mac, add-cpe-id, or add-subnet.

CVE-2017-14496: An integer underflow flaw leading to a buffer over-read was found in dnsmasq in the EDNS0 code. An attacker could send crafted DNS packets to dnsmasq which would cause it to crash. This issue only affected configurations using one of the options: add-mac, add-cpe-id, or add-subnet.

An audit by mozilla security found several vulnerability and potential vulnerability in dnsmasq:

• Uninitialized buffer leads to memory leakage
• Allocated memory is not cleared
• Unchecked return value can lead to NULL pointer dereference
• Hardcoded values in fscanf() format strings with aliased buffers

CVE-2017-13704: Dnsmasq could be made to crash on a large DNS query: A DNS query received by UDP which exceeds 512 bytes (or the EDNS0 packet size, if different.) is enough to cause SIGSEGV. (bug 21793)

CVE-2017-14491: A heap buffer overflow was found in dnsmasq in the code responsible for building DNS replies. An attacker could send crafted DNS packets to dnsmasq which would cause it to crash or, potentially, execute arbitrary code.

CVE-2017-14492: A heap buffer overflow was discovered in dnsmasq in the IPv6 router advertisement (RA) handling code. An attacker on the local network segment could send crafted RAs to dnsmasq which would cause it to crash or, potentially, execute arbitrary code. This issue only affected configurations using one of these options: enable-ra, ra-only, slaac, ra-names, ra-advrouter, or ra-stateless.

CVE-2017-14493: A stack buffer overflow was found in dnsmasq in the DHCPv6 code. An attacker on the local network could send a crafted DHCPv6 request to dnsmasq which would cause it to a crash or, potentially, execute arbitrary code.

CVE-2017-14494: An information leak was found in dnsmasq in the DHCPv6 relay code. An attacker on the local network could send crafted DHCPv6 packets to dnsmasq causing it to forward the contents of process memory, potentially leaking sensitive data.

CVE-2017-14495: A memory exhaustion flaw was found in dnsmasq in the EDNS0 code. An attacker could send crafted DNS packets which would trigger memory allocations which would never be freed, leading to unbounded memory consumption and eventually a crash. This issue only affected configurations using one of the options: add-mac, add-cpe-id, or add-subnet.

CVE-2017-14496: An integer underflow flaw leading to a buffer over-read was found in dnsmasq in the EDNS0 code. An attacker could send crafted DNS packets to dnsmasq which would cause it to crash. This issue only affected configurations using one of the options: add-mac, add-cpe-id, or add-subnet.