CLD-243 Details

Other IDs this deficiency may be known by:

CVE ID CVE-2018-1000007 (nvd) (mitre) (debian) (archlinux) (red hat) (suse) (ubuntu)
Other ID(s)

Basic Information:

Affected Package(s) curl
Deficiency Type SECURITY
Date Created 2018-01-24 09:06:18
Date Last Modified 2018-01-24 09:27:09

Version Specific Information:

Cucumber 1.0 i686fixed in curl-7.58.0-i686-1
Cucumber 1.0 x86_64fixed in curl-7.58.0-x86_64-1 and curl-lib_i686-7.58.0-lib_i686-1

Cucumber 1.1 i686 fixed in curl-7.58.0-i686-1
Cucumber 1.1 x86_64 fixed in curl-7.58.0-x86_64-1 and curl-lib_i686-7.58.0-lib_i686-1


================================ Initial Report ================================


HTTP authentication leak in redirects

Project curl Security Advisory, January 24th 2018 -


libcurl might leak authentication data to third parties.

When asked to send custom headers in its HTTP requests, libcurl will send that
set of headers first to the host in the initial URL but also, if asked to
follow redirects and a 30X HTTP response code is returned, to the host
mentioned in URL in the `Location:` response header value.

Sending the same set of headers to subsequest hosts is in particular a problem
for applications that pass on custom `Authorization:` headers, as this header
often contains privacy sensitive information or data that could allow others
to impersonate the libcurl-using client's request.

We are not aware of any exploit of this flaw.


This bug has existed since before curl 6.0. It existed in the first commit we
have recorded in the project.

The Common Vulnerabilities and Exposures (CVE) project has assigned the name
CVE-2018-1000007 to this issue.


- Affected versions: libcurl 7.1 to and including 7.57.0
- Not affected versions: libcurl >= 7.58.0

libcurl is used by many applications, but not always advertised as such.


In libcurl version 7.58.0, custom `Authorization:` headers will be limited the
same way other such headers is controlled within libcurl: they will only be
sent to the host used in the original URL unless libcurl is told that it is ok
to pass on to others using the `CURLOPT_UNRESTRICTED_AUTH` option.

**NOTE**: this solution creates a slight change in behavior. Users who
actually want to pass on the header to other hosts now need to give curl that
specific permission. You do this with
with the curl command line tool.

A [patch for
is available.


We suggest you take one of the following actions immediately, in order of

 A - Upgrade curl to version 7.58.0

 B - Apply the patch to your version and rebuild

 C - Do not enable CURLOPT_FOLLOWLOCATION if you pass on custom Authorization


It was reported to the curl project on January 18, 2018

We contacted distros@openwall on January 19.

curl 7.58.0 was released on January 24 2018, coordinated with the publication
of this advisory.


Reported by Craig de Stigter. Patch by Daniel Stenberg.

Thanks a lot!



================================= Our Analysis =================================

----- Affected Products -----
Versions of curl < 7.58.0 and > 7.49.0 are affected. This includes curl as
originally packaged in Cucumber Linux 1.0 and 1.1.

----- Fix for this Vulnerability -----
This vulnerability has been fixed in curl 7.58.0.

================================= Our Solution =================================

We have upgraded to curl 7.58.0.