curl versions 7.54.1 through 7.60.0 are vulnerable to a heap-based buffer overflow in the Curl_smtp_escape_eob() function when uploading data over SMTP and using a reduced read buffer. An attacker could exploit this by convincing a user to use curl to upload data over SMTP with a reduced buffer to cause a crash or corrupt memory.
Flaw introduced by: https://github.com/curl/curl/commit/e40e9d7f0decc79
Created attachment 1456079 [details] Upstream patch
Acknowledgments: Name: the Curl project Upstream: Peter Wu
Even though some versions shipped in RHEL and in RHSCL 3 provide the option to reduce the read buffer, they are not vulnerable to this flaw because they do not use the buffer size value to allocate the scratch buffer in Curl_smtp_escape_eob.
Statement: This issue did not affect the versions of curl/libcurl as shipped with Red Hat Enterprise Linux 5, 6 and 7 as they did not include the vulnerable code. This issue did not affect the versions of curl/libcurl as shipped with Red Hat Software Collections 3 as they did not include the vulnerable code.
Patch: https://github.com/curl/curl/commit/ba1dbd78e5f1e
External References: https://curl.haxx.se/docs/adv_2018-70a2.html
Created curl tracking bugs for this issue: Affects: fedora-all [bug 1600081]
This issue has been addressed in the following products: Red Hat JBoss Core Services Via RHSA-2018:2486 https://access.redhat.com/errata/RHSA-2018:2486