Archive for the ‘General’ Category

Launchpad news, June 2018

Friday, July 6th, 2018

Here’s a brief changelog for this month.

(more…)

Launchpad news, May 2018

Saturday, June 2nd, 2018

Here’s a brief changelog for this month.

(more…)

Launchpad news, June 2017 – April 2018

Tuesday, May 1st, 2018

Once again it’s been a while since we posted a general update, so here’s a changelog-style summary of what we’ve been up to.  As usual, this changelog preserves a reasonable amount of technical detail, but I’ve omitted changes that were purely internal refactoring with no externally-visible effects.

(more…)

Launchpad security advisory: cross-site-scripting in site search

Wednesday, April 11th, 2018

Summary

Mohamed Alaa reported that Launchpad’s Bing site search implementation had a cross-site-scripting vulnerability.  This was introduced on 2018-03-29, and fixed on 2018-04-10.  We have not found any evidence of this bug being actively exploited by attackers; the rest of this post is an explanation of the problem for the sake of transparency.

Details

Some time ago, Google announced that they would be discontinuing their Google Site Search product on 2018-04-01.  Since this served as part of the backend for Launchpad’s site search feature (“Search Launchpad” on the front page), we began to look around for a replacement.  We eventually settled on Bing Custom Search, implemented appropriate support in Launchpad, and switched over to it on 2018-03-29.

Unfortunately, we missed one detail.  Google Site Search’s XML API returns excerpts of search results as pre-escaped HTML, using <b> tags to indicate where search terms match.  This makes complete sense given its embedding in XML; it’s hard to see how that API could do otherwise.  The Launchpad integration code accordingly uses TAL code along these lines, using the structure keyword to explicitly indicate that the excerpts in question do not require HTML-escaping (like most good web frameworks, TAL’s default is to escape all variable content, so successful XSS attacks on Launchpad have historically been rare):

<div class="summary" tal:content="structure page/summary" />

However, Bing Custom Search’s JSON API returns excerpts of search results without any HTML escaping.  Again, in the context of the API in question, this makes complete sense as a default behaviour (though a textFormat=HTML switch is available to change this); but, in the absence of appropriate handling, this meant that those excerpts were passed through to the TAL code above without escaping.  As a result, if you could craft search terms that match a portion of an existing page on Launchpad that shows scripting tags (such as a bug about an XSS vulnerability in another piece of software hosted on Launchpad), and convince other people to follow a suitable search link, then you could cause that code to be executed in other users’ browsers.

The fix was, of course, to simply escape the data returned by Bing Custom Search.  Thanks to Mohamed Alaa for their disclosure.

Launchpad news, May 2017

Wednesday, May 31st, 2017

Here’s a brief changelog for this month.

(more…)

Launchpad news, November 2015 – April 2017

Friday, April 28th, 2017

Well, it’s been a while!  Since we last posted a general update, the Launchpad team has become part of Canonical’s Online Services department, so some of our efforts have gone into other projects.  There’s still plenty happening with Launchpad, though, and here’s a changelog-style summary of what we’ve been up to.

(more…)

Launchpad news, October 2015

Monday, November 9th, 2015

Here’s what the Launchpad team did in October.

(more…)

Beta test: webhooks

Monday, November 9th, 2015

If you are a member of Launchpad’s beta testers team, you can now try out webhooks for Bazaar branches and Git repositories. These can be used to set up integration with external sites for various purposes, such as running CI jobs or publishing documentation. We expect to open this up to all Launchpad users soon, but in the meantime please do file a bug against Launchpad itself if you encounter any problems.

See our webhooks documentation for more details.

Update: as of 2015-11-20, this feature is enabled for all Launchpad users.

Launchpad news, September 2015

Sunday, October 4th, 2015

October already! As the leaves start to turn red here in the northern hemisphere, here’s a brief summary of what we did in September.

(more…)

Launchpad news, August 2015

Wednesday, September 2nd, 2015

Here’s a summary of what the Launchpad team got up to in August.

(more…)