[SECURITY ADVISORY] curl: FTP-KRB bad message verification

[Daniel Stenberg <daniel () haxx se>]

CVE-2022-32208: FTP-KRB bad message verification
================================================

Project curl Security Advisory, June 27th 2022 -
[Permalink](https://curl.se/docs/CVE-2022-32208.html)

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

When curl does FTP transfers secured by krb5, it handles message verification
failures wrongly. This flaw makes it possible for a Man-In-The-Middle attack
to go unnoticed and even allows it to inject data to the client.

We are not aware of any exploit of this flaw.

INFO
----

CVE-2022-32208 was introduced in [commit
54967d2a3a](https://github.com/curl/curl/commit/54967d2a3a), shipped
in curl 7.16.4.

This flaw typically makes curl insert `599 ` (+ terminating null) into the
data where it detects the error, then the attackers data. It forces the
attacker to be somewhat creative to handle this initial hard-coded 5 byte
sequence of "junk".

FTP-KRB is a rarely used feature.

CWE-924: Improper Enforcement of Message Integrity During Transmission in a
Communication Channel

Severity: Low

AFFECTED VERSIONS
-----------------

- Affected versions: curl 7.16.4 to and including 7.83.1
- Not affected versions: curl < 7.16.4 and curl >= 7.84.0

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

THE SOLUTION
------------

A [fix for CVE-2022-32208](https://github.com/curl/curl/commit/6ecdf5136b52af7)

RECOMMENDATIONS
--------------

 A - Upgrade curl to version 7.84.0

 B - Apply the patch to your local version

 C - Do not use KRB-FTP

TIMELINE
--------

This issue was reported to the curl project on June 2, 2022. We contacted
distros@openwall on June 20.

libcurl 7.84.0 was released on June 27 2022, coordinated with the publication
of this advisory.

CREDITS
-------

This issue was reported by Harry Sintonen. Patched by Daniel Stenberg.

Thanks a lot!

--

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