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[$] Fedora 40 firms up for release
Fedora 40 Beta was released on March 26, and the final release is nearing completion. So far, the release is coming together nicely with major updates for GNOME, KDE Plasma, and the usual cavalcade of smaller updates and enhancements. As part of the release, the project also scuttled Delta RPMs and OpenSSL 1.1.
PuTTY 0.81 security release
PuTTY 0.81, released today, fixes a critical vulnerability CVE-2024-31497 in the use of 521-bit ECDSA keys (ecdsa-sha2-nistp521). If you have used a 521-bit ECDSA private key with any previous version of PuTTY, consider the private key compromised: remove the public key from authorized_keys files, and generate a new key pair.
However, this only affects that one algorithm and key size. No other size of ECDSA key is affected, and no other key type is affected.
Security updates for Tuesday
OpenSSF and OpenJS warn about social-engineering attacks
The OpenJS Foundation Cross Project Council received a suspicious series of emails with similar messages, bearing different names and overlapping GitHub-associated emails. These emails implored OpenJS to take action to update one of its popular JavaScript projects to "address any critical vulnerabilities," yet cited no specifics. The email author(s) wanted OpenJS to designate them as a new maintainer of the project despite having little prior involvement.
[$] Cleaning up after BPF exceptions
Kumar Kartikeya Dwivedi has been working to add support for exceptions to BPF since mid-2023. In July, Dwivedi posted the first patch set in this effort, which adds support for basic stack unwinding. In February 2024, he posted the second patch set aimed at letting the kernel release resources held by the BPF program when an exception occurs. This makes exceptions usable in many more contexts.
Security updates for Monday
Kernel prepatch 6.9-rc4
Saturday's stable kernel updates
[$] A tale of two troublesome drivers
What we need to take away from the XZ Backdoor (openSUSE News)
Debian, as well as the other affected distributions like openSUSE are carrying a significant amount of downstream-only patches to essential open-source projects, like in this case OpenSSH. With hindsight, that should be another Heartbleed-level learning for the work of the distributions. These patches built the essential steps to embed the backdoor, and do not have the scrutiny that they likely would have received by the respective upstream maintainers. Whether you trust Linus Law or not, it was not even given a chance to chime in here. Upstream did not fail on the users, distributions failed on upstream and their users here.
Security updates for Friday
[$] Completing the EEVDF scheduler
Security updates for Thursday
[$] LWN.net Weekly Edition for April 11, 2024
Gentoo Linux becomes an SPI Associated Project
The Gentoo Linux project has announced that it is now an Associated Project of Software in the Public Interest (SPI), which will allow it to accept tax deductible donations in the US and reduce its "non-technical workload":
The current Gentoo Foundation has bylaws restricting its behavior to that of a non-profit, is a recognized non-profit only in New Mexico, but a for-profit entity at the US federal level. A direct conversion to a federally recognized non-profit would be unlikely to succeed without significant effort and cost.
[...] SPI is already now recognized at US federal level as a full-[fledged] non-profit 501(c)(3). It also handles several projects of similar type and size (e.g., Arch and Debian) and as such has exactly the experience and background that Gentoo needs.
According to the announcement, the goal is to "eventually transfer the existing assets to SPI and dissolve the Gentoo Foundation". How to do that is still under discussion. This will not affect Förderverein Gentoo e.V., which has public-benefit status in Germany and can accept tax deductible donations in Europe.
Four stable kernel updates
Greg Kroah-Hartman has announced another round of stable kernel updates: 6.8.5, 6.6.26, 6.1.85, and 5.15.154 have all been released; each contains another set of important fixes, including the mitigations for the recently disclosed branch history injection hardware vulnerability.
[$] Book review: Practical Julia
[$] Continued attacks on HTTP/2
On April 3 security researcher Bartek Nowotarski published the details of a new denial-of-service (DoS) attack, called a "continuation flood", against many HTTP/2-capable web servers. While the attack is not terribly complex, it affects many independent implementations of the HTTP/2 protocol, even though multiple similar vulnerabilities over the years have given implementers plenty of warning.
Security updates for Wednesday
The "branch history injection" hardware vulnerability
Branch History Injection (BHI) attacks may allow a malicious application to influence indirect branch prediction in kernel by poisoning the branch history. eIBRS isolates indirect branch targets in ring0. The BHB can still influence the choice of indirect branch predictor entry, and although branch predictor entries are isolated between modes when eIBRS is enabled, the BHB itself is not isolated between modes.
See this commit for documentation on the command-line parameter that controls this mitigation. There are stable kernel releases (6.8.5, 6.6.26, 6.1.85, and 5.15.154) in the works that also contain the mitigations.