The libcurl API function called `curl_maprintf()` before version 7.51.0 can be tricked into doing a double-free due to an unsafe `size_t` multiplication, on systems using 32 bit `size_t` variables.
The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.
The product calls free() twice on the same memory address.
| Link | Tags |
|---|---|
| https://access.redhat.com/errata/RHSA-2018:3558 | vendor advisory |
| https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2016-8618 | issue tracking third party advisory patch |
| https://www.tenable.com/security/tns-2016-21 | third party advisory |
| http://www.securitytracker.com/id/1037192 | vdb entry third party advisory |
| http://www.oracle.com/technetwork/security-advisory/cpuoct2018-4428296.html | |
| https://curl.haxx.se/docs/adv_20161102D.html | patch vendor advisory |
| https://access.redhat.com/errata/RHSA-2018:2486 | third party advisory vendor advisory |
| https://security.gentoo.org/glsa/201701-47 | third party advisory vendor advisory |
| http://www.securityfocus.com/bid/94098 | vdb entry third party advisory |