Arch Linux Security Advisory ASA-201609-18 ========================================== Severity: Low Date : 20916-09-20 CVE-ID : CVE-2016-7167 Package : lib32-curl Type : denial of service Remote : Yes Link : https://wiki.archlinux.org/index.php/CVE Summary ======= The package lib32-curl before version 7.50.3-1 is vulnerable to denial of service. Resolution ========== Upgrade to 7.50.3-1. # pacman -Syu "lib32-curl>=7.50.3-1" The problem has been fixed upstream in version 7.50.3. Workaround ========== None. Description =========== The four libcurl functions `curl_escape()`, `curl_easy_escape()`, `curl_unescape` and `curl_easy_unescape` perform string URL percent escaping and unescaping. They accept custom string length inputs in signed integer arguments. (The functions having names without "easy" being the deprecated versions of the others.) The provided string length arguments were not properly checked and due to arithmetic in the functions, passing in the length 0xffffffff (2^32-1 or `UINT_MAX` or even just -1) would end up causing an allocation of zero bytes of heap memory that curl would attempt to write gigabytes of data into. The use of 'int' for this input type in the API is of course unwise but has remained so in order to maintain the API over the years. We are not aware of any exploit of this flaw. Impact ====== A remote attacker might cause a crash by providing a specially crafted URL, leading to a denial of service. References ========== http://www.openwall.com/lists/oss-security/2016/09/14/1 https://curl.haxx.se/docs/adv_20160914.html https://access.redhat.com/security/cve/CVE-2016-7167