Follow @Openwall on Twitter for new release announcements and other news
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date: Thu, 13 Jan 2022 15:23:11 +0100
From: Jonas Schäfer <jonas@...licki.name>
To: oss-security@...ts.openwall.com
Subject: Re: Prosody XMPP server advisory 2022-01-13 (Remote Unauthenticated Denial of Service) (CVE request)

Hi, quick update:

On Donnerstag, 13. Januar 2022 15:01:11 CET Jonas Schäfer wrote:
> If neither patching nor upgrading is an option, it is possible to unload
> the websocket module using:
> 
> ```
> prosodyctl shell module unload websocket
> ```

This only works on recent Prosody trunk. On 0.11.x and earlier, you need to 

- use module:unload("websocket") from the telnet console, OR
- unload the module via an XMPP Ad-Hoc command OR
- if neither of these online ways are available, remove the module from the 
configuration and restart prosody.

kind regards,
Jonas

> 
> However, note well that third-party modules may also use the vulnerable
> internal APIs to parse XML. Unloading websocket does not protect those
> other modules; only the patch or the upgrade can do that.
> 
> **Fix**
> 
> This issue is fixed in Prosody 0.11.12 by restricting the available XML
> features in the internal XML API.
> 
> **Attribution**
> 
> The issue was discovered during internal code review by Matthew Wild
> during the development of another feature. The patch was developed by
> Jonas Schäfer. A proof-of-concept exploit was developed by Jonas Schäfer
> and Kim Alvefur and will be published soon to allow administrators to
> check their instances.
> 
> **Timeline**
> 
> 2022-01-10: Discovery of the issue, development of an exploit as well as
> an initial patch. Sharing of this information with Jitsi and Snikket
> developers. Heads-up sent to the Snikket group chat.
> 
> 2022-01-11: Refinement of the patch, release preparation. Heads-up sent
> to the Prosody group chat. Patch shared confidentially with Jitsi.
> 
> 2022-01-12: Continued release preparation, notification of distros@.
> 
> 2022-01-13: Coordinated Snikket and Prosody release with a
> fix, publication of the advisory.


Download attachment "signature.asc" of type "application/pgp-signature" (834 bytes)

Powered by blists - more mailing lists

Please check out the Open Source Software Security Wiki, which is counterpart to this mailing list.

Confused about mailing lists and their use? Read about mailing lists on Wikipedia and check out these guidelines on proper formatting of your messages.