curl / Mailing Lists / curl-library / Single Mail

curl-library

[SECURITY ADVISORY] curl: SMTP end-of-response out-of-bounds read

From: Daniel Stenberg via curl-library <curl-library_at_cool.haxx.se>
Date: Wed, 6 Feb 2019 08:12:37 +0100 (CET)

SMTP end-of-response out-of-bounds read
=======================================

Project curl Security Advisory, February 6th 2019 -
[Permalink](https://curl.haxx.se/docs/CVE-2019-3823.html)

VULNERABILITY
-------------

libcurl contains a heap out-of-bounds read in the code handling the
end-of-response for SMTP.

If the buffer passed to `smtp_endofresp()` isn't NUL terminated and contains
no character ending the parsed number, and `len` is set to 5, then the
`strtol()` call reads beyond the allocated buffer. The read contents will not
be returned to the caller.

We are not aware of any exploit of this flaw.

INFO

----
This bug was introduced in October 2013 in
[commit 2766262a68](https://github.com/curl/curl/commit/2766262a68).
The Common Vulnerabilities and Exposures (CVE) project has assigned the name
CVE-2019-3823 to this issue.
CWE-125: Out-of-bounds Read
Severity: 3.7 (Low)
AFFECTED VERSIONS
-----------------
- Affected versions: libcurl 7.34.0 to and including 7.63.0
- Not affected versions: libcurl < 7.34.0
libcurl is used by many applications, but not always advertised as such.
THE SOLUTION
------------
A [patch for CVE-2019-3823](https://github.com/curl/curl/commit/39df4073e5413fcdbb5a38da0c1ce6f1c0ceb484) is available.
RECOMMENDATIONS
--------------
We suggest you take one of the following actions immediately, in order of
preference:
  A - Upgrade curl to version 7.64.0
  B - Apply the patch to your version and rebuild
  C - Turn off SMTP
TIMELINE
--------
The issue was reported to the curl project on January 18, 2019. A patch was
communicated to the reporter on January 19, 2019. We contacted distros_at_openwall
on January 28.
curl 7.64.0 was released on February 6 2019, coordinated with the publication
of this advisory.
CREDITS
-------
Reported by Brian Carpenter, Geeknik Labs. Patch by Daniel Gustafsson
Thanks a lot!
-- 
  / daniel.haxx.se
-------------------------------------------------------------------
Unsubscribe: https://cool.haxx.se/list/listinfo/curl-library
Etiquette:   https://curl.haxx.se/mail/etiquette.html
Received on 2019-02-06