MD-2023-1018#

Statement on MD-2023-1018 Curl, Libcurl Vulnerability#

October 18, 2023

Information#

This flaw allows an attacker to insert cookies at will into a running program using libcurl, if the specific series of conditions are met. libcurl performs transfers. In its API, an application creates “easy handles” that are the individual handles for single transfers. libcurl provides a function call that duplicates en easy handle called [curl_easy_duphandle](https://curl.se/libcurl/c/curl_easy_duphandle.html). If a transfer has cookies enabled when the handle is duplicated, the cookie-enable state is also cloned - but without cloning the actual cookies. If the source handle did not read any cookies from a specific file on disk, the cloned version of the handle would instead store the file name as none (using the four ASCII letters, no quotes). Subsequent use of the cloned handle that does not explicitly set a source to load cookies from would then inadvertently load cookies from a file named none - if such a file exists and is readable in the current directory of the program using libcurl. And if using the correct file format of course.

Severity#

Low

Response#

Melissa Data Corporation (“Melissa”) was not impacted by Curl, Libcurl Vulnerability. The Curl version being used by Melissa was not affected by this vulnerability.

Melissa will continue to follow all guidance provided for this vulnerability as necessary to prevent any future risks.