Arch Linux Security Advisory ASA-201805-16 ========================================== Severity: Critical Date : 2018-05-18 CVE-ID : CVE-2018-1000300 CVE-2018-1000301 Package : lib32-libcurl-gnutls Type : multiple issues Remote : Yes Link : https://security.archlinux.org/AVG-697 Summary ======= The package lib32-libcurl-gnutls before version 7.60.0-1 is vulnerable to multiple issues including arbitrary code execution and denial of service. Resolution ========== Upgrade to 7.60.0-1. # pacman -Syu "lib32-libcurl-gnutls>=7.60.0-1" The problems have been fixed upstream in version 7.60.0. Workaround ========== None. Description =========== - CVE-2018-1000300 (arbitrary code execution) curl >= 7.54.1 and < 7.60.0 might overflow a heap based memory buffer when closing down an FTP connection with very long server command replies. When doing FTP transfers, curl keeps a spare "closure handle" around internally that will be used when an FTP connection gets shut down since the original curl easy handle is then already removed. FTP server response data that gets cached from the original transfer might then be larger than the default buffer size (16 KB) allocated in the "closure handle", which can lead to a buffer overwrite. The contents and size of that overwrite is controllable by the server. - CVE-2018-1000301 (denial of service) curl >= 7.20.0 and < 7.60.0 can be tricked into reading data beyond the end of a heap based buffer used to store downloaded content. When servers send RTSP responses back to curl, the data starts out with a set of headers. curl parses that data to separate it into a number of headers to deal with those appropriately and to find the end of the headers that signal the start of the "body" part. The function that splits up the response into headers is called Curl_http_readwrite_headers() and in situations where it can't find a single header in the buffer, it might end up leaving a pointer pointing into the buffer instead of to the start of the buffer which then later on may lead to an out of buffer read when code assumes that pointer points to a full buffer size worth of memory to use. This could potentially lead to information leakage but most likely a crash/denial of service for applications if a server triggers this flaw. Impact ====== A malicious, remote server can cause a denial of service via a crafted RTSP answer, and execute arbitrary code on the affected host via a crafted FTP answer. References ========== https://curl.haxx.se/docs/adv_2018-82c2.html https://curl.haxx.se/CVE-2018-1000300.patch https://curl.haxx.se/docs/adv_2018-b138.html https://curl.haxx.se/CVE-2018-1000301.patch https://security.archlinux.org/CVE-2018-1000300 https://security.archlinux.org/CVE-2018-1000301