Arch Linux Security Advisory ASA-201710-1 ========================================= Severity: Critical Date : 2017-10-02 CVE-ID : CVE-2017-14491 CVE-2017-14492 CVE-2017-14493 CVE-2017-14494 CVE-2017-14495 CVE-2017-14496 Package : dnsmasq Type : multiple issues Remote : Yes Link : https://security.archlinux.org/AVG-421 Summary ======= The package dnsmasq before version 2.78-1 is vulnerable to multiple issues including arbitrary code execution, denial of service and information disclosure. Resolution ========== Upgrade to 2.78-1. # pacman -Syu "dnsmasq>=2.78-1" The problems have been fixed upstream in version 2.78. Workaround ========== None. Description =========== - CVE-2017-14491 (arbitrary code execution) 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 (arbitrary code execution) 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 (arbitrary code execution) 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 (information disclosure) 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 (denial of service) 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 (denial of service) 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. Impact ====== A remote attacker is able to execute arbitrary code, disclose sensitive information or crash the application by sending specially crafted packets. References ========== https://security.googleblog.com/2017/10/behind-masq-yet-more-dns-and-dhcp.ht... https://github.com/google/security-research-pocs/tree/master/vulnerabilities... http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commitdiff;h=0549c73b7ea6b2... http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commitdiff;h=62cb936cb7ad5f... http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commitdiff;h=24036ea507862c... http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commitdiff;h=3d4ff1ba841954... http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commitdiff;h=33e3f1029c9ec6... http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commitdiff;h=51eadb692a5123... http://thekelleys.org.uk/gitweb/?p=dnsmasq.git;a=commitdiff;h=897c113fda0886... https://security.archlinux.org/CVE-2017-14491 https://security.archlinux.org/CVE-2017-14492 https://security.archlinux.org/CVE-2017-14493 https://security.archlinux.org/CVE-2017-14494 https://security.archlinux.org/CVE-2017-14495 https://security.archlinux.org/CVE-2017-14496