Tag Archives: xsa

Request for Comment: Scope of Vulnerabilities for which XSAs are issued

Issuing advisories has a cost: It costs the security team significant amounts of time to craft and send the advisories; it costs many of our downstreams time to apply, build, and test patches; and it costs many of our users time to decide whether to do an update, and if so, to test and deploy it.

Given this, the Xen Project Security Team wants to clarify when they should issue an advisory or not: the Xen Security Response Process only mentions “‘vulnerabilities”, without specifying what constitutes a vulnerability.

We would like guidelines from the community about what sorts of issues should be considered security issues (and thus will have advisories issued). I have posted the second version a draft of a section I am proposing to be added to the Xen Security Policy to xen-devel; a copy is included below for your convenience. There are only minor modifications from the first draft, so barring major feedback from the wider community it will likely achieve consensus. If you want input, now is the time to speak up.

Most of it is just encoding long-established practice. But there are two key changes and / or clarifications that deserve attention and discussion:

    Criteria 2c: Leaking of mundane information from Xen or dom0 will not be considered a security issue unless it may contain sensitive guest or user data

Criteria 4: If no operating systems are vulnerable to a bug, no advisory will be issued.

If you want to weigh in on the question, please join the discussion on xen-devel before 28 February. The title of the thread is “RFC v2: Scope of Vulnerabilities for which XSAs are issued”.

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What You Need to Know about Recent Xen Project Security Advisories

Today the Xen Project announced eight security advisories: XSA-191 to XSA-198. The bulk of these security advisories were discovered and fixed during the hardening phase of the Xen Project Hypervisor 4.8 release (expected to come out in early December). The Xen Project has implemented a security-first approach when publishing new releases.

In order to increase the security of future releases, members of the Xen Project Security Team and key contributors to the Xen Project, actively search and fix security bugs in code areas where vulnerability were found in past releases. The contributors use techniques such as code inspections, static code analysis, and additional testing using fuzzers such as American Fuzzy Lop. These fixes are then backported to older Xen Project releases with security support and published in bulk to make it easier for downstreams consumers to apply security fixes.

Before we declare a new Xen Project feature as supported, we perform a security assessment (see declare the Credit2 scheduler as supported). In addition, the contributors focused on security have started crafting tests for each vulnerability and integrated them into our automated regression testing system run regularly on all maintained versions of Xen. This ensures that the patch will be applied to every version which is vulnerable, and also ensures that no bug is accidentally reintroduced as development continues to go forward.

The Xen Project’s mature and robust security response process is optimized for cloud environments and downstream Xen Project consumers to maximize fairness, effectiveness and transparency. This includes not publicly discussing any details with security implications during our embargo period. This encourages anyone to report bugs they find to the Xen Project Security team, and allows the Xen Project Security team to assess, respond, and prepare patches, before before public disclosure and broad compromise occurs.

During the embargo period, the Xen Project does not publicly discuss any details with security implications except:

  • when co-opting technical assistance from other parties;
  • when issuing a Xen Project Security Advisory (XSA). This is pre-disclosed to only members on the Xen Project Pre-Disclosure List (see www.xenproject.org/security-policy.html); and
  • when necessary to coordinate with other projects affected

The Xen Project security team will assign and publicly release numbers for vulnerabilities. This is the only information that is shared publicly during the embargo period. See this url for “XSA Advisories, Publicly Released or Pre-Released”: xenbits.xen.org/xsa.

Xen’s latest XSA-191, XSA-192, XSA-193, XSA-194, XSA-195, XSA-196, XSA-197 and XSA-198 Advisory can all be found here:
xenbits.xen.org/xsa

Any Xen-based public cloud is eligible to be on our “pre-disclosure” list. Cloud providers on the list were notified of the vulnerability and provided a patch two weeks before the public announcement in order to make sure they all had time to apply the patch to their servers.

Distributions and other major software vendors of Xen Project software were also given the patch in advance to make sure they had updated packages ready to download as soon as the vulnerability was announced. Private clouds and individuals are urged to apply the patch or update their packages as soon as possible.

All of the above XSAs that affect the hypervisor can be deployed using the Xen Project LivePatching functionality, which enables re-boot free deployment of security patches to minimize disruption and downtime during security upgrades for system administrators and DevOps practitioners. The Xen Project encourages its users to download these patches.

More information about the Xen Project’s Security Vulnerability Process, including the embargo and disclosure schedule, policies around embargoed information, information sharing among pre-disclosed list members, a list of pre-disclosure list members, and the application process to join the list, can be found at: www.xenproject.org/security-policy.html

Xen Directions South America Agenda Announcement

Xen Directions South America is 1 month away and I am pleased to release the current agenda which is in final review with the event organizers and Linuxcon Brazil team.

Agenda

I will be updating the event home page at http://www.xen.org/community/xenevents.html with this agenda next week once it is finalized. I also will publish the speaker profile document at that time as well.

Looking forward to seeing everyone in Brazil next month.

Xen Summit North America at AMD – Agenda Announced

The final (or just about final) agenda for Xen Summit North America at AMD is now available. The agenda has 26 presentations over 2 days (April 28-29) and provides attendees with a variety of topics of interest to the Xen.org community. Speaker profiles and topic abstracts are also now available for your consumption.

You can register for $235 at http://www.regonline.com/xen_summit_amd.

Agenda Available for Xen Summit at Oracle

The final agenda for Xen Summit at Oracle is available at http://www.xen.org/files/xensummit_oracle09/xensummit_agenda.pdf.

The abstracts are also available at http://www.xen.org/files/xensummit_oracle09/xensummit_abstracts.pdf.

Speaker profiles at http://www.xen.org/files/xensummit_oracle09/xensummit_speakers.pdf.

Registration is $215 here. I look forward to seeing everyone in California in a few weeks.