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Linux Random Number Generator Sees Major Improvements
by Peter Reutemann 22 Mar '22

22 Mar '22

'An anonymous Slashdot reader summarizes some important news from the web page of Jason Donenfeld (creator of the open-source VPN protocol WireGuard): The Linux kernel's random number generator has seen its first set of major improvements in over a decade, improving everything from the cryptography to the interface used. Not only does it finally retire SHA-1 in favor of BLAKE2s [in Linux kernel 5.17], but it also at long last unites '/dev/random' and '/dev/urandom' [in the upcoming Linux kernel 5.18], finally ending years of Slashdot banter and debate: The most significant outward-facing change is that /dev/random and /dev/urandom are now exactly the same thing, with no differences between them at all, thanks to their unification in random: block in /dev/urandom. This removes a significant age-old crypto footgun, already accomplished by other operating systems eons ago. [...] The upshot is that every Internet message board disagreement on /dev/random versus /dev/urandom has now been resolved by making everybody simultaneously right! Now, for the first time, these are both the right choice to make, in addition to getrandom(0); they all return the same bytes with the same semantics. There are only right choices. Phoronix adds: One exciting change to also note is the getrandom() system call may be a hell of a lot faster with the new kernel. The getrandom() call for obtaining random bytes is yielding much faster performance with the latest code in development. Intel's kernel test robot is seeing an 8450% improvement with the stress-ng getrandom() benchmark. Yes, an 8450% improvement.' -- source: https://linux.slashdot.org/story/22/03/19/1821254 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 (office) +64 (7) 577-5304 (home office) https://www.cs.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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KDE Konsole Shows Colours!
by Lawrence D'Oliveiro 22 Mar '22

22 Mar '22

I noticed this happening in my Konsole terminal windows very occasionally over the last couple of months: a little coloured square with a black border would momentarily appear, then disappear when I moved the mouse. I never quite figured out what was going on, thought it was a window manager glitch or something ... until today. It appears Konsole has this (undocumented?) feature where, if you hover over the name of a colour in a terminal session, it will helpfully pop up this square showing what the colour looks like. The colour names come from the traditional X11 set in /usr/share/X11/rgb.txt, with limits: it only looks at single-word names, and does not match names with numeric suffixes. Thus, “darkmagenta” will work (case-insensitive match against “DarkMagenta”), while “dark magenta” only matches the “magenta” part, and “magenta1” is not recognized at all. It will also recognize a sequence of 3 or 6 hex digits preceded by “#” -- “#rgb” or “#rrggbb”, as commonly used in HTML. Just tried 8 hex digits -- “#rrggbbaa” with alpha transparency -- and that works too. This feature might be new in Konsole 21.08 or something.

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Browser-in-the-Browser Attack Can Trick Even Savvy Users
by Peter Reutemann 22 Mar '22

22 Mar '22

'Ars Technica: Hundreds of thousands of sites use the OAuth protocol to let visitors login using their existing accounts with companies like Google, Facebook, or Apple. Instead of having to create an account on the new site, visitors can use an account that they already have -- and the magic of OAuth does the rest. The Browser-in-the-Browser (BitB) technique capitalizes on this scheme. Instead of opening a genuine second browser window that's connected to the site facilitating the login or payment, BitB uses a series of HTML and cascading style sheets (CSS) tricks to convincingly spoof the second window. The URL that appears there can show a valid address, complete with a padlock and HTTPS prefix. The layout and behavior of the window appear identical to the real thing. While the method is convincing, it has a few weaknesses that should give savvy visitors a foolproof way to detect that something is amiss. Genuine OAuth or payment windows are in fact separate browser instances that are distinct from the primary page. That means a user can resize them and move them anywhere on the monitor, including outside the primary window. BitB windows, by contrast, aren't a separate browser instance at all. Instead, they're images rendered by custom HTML and CSS and contained in the primary window. That means the fake pages can't be resized, fully maximized or dragged outside the primary window. All users should protect their accounts with two-factor authentication. One other thing more experienced users can do is right click on the popup page and choose "inspect." If the window is a BitB spawn, its URL will be hardcoded into the HTML. ' -- source: https://it.slashdot.org/story/22/03/21/236242 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 (office) +64 (7) 577-5304 (home office) https://www.cs.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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A big bet to kill the password for good
by Peter Reutemann 21 Mar '22

21 Mar '22

'After years of tantalizing hints that a passwordless future is just around the corner, you're probably still not feeling any closer to that digital unshackling. Ten years into working on the issue, though, the FIDO Alliance, an industry association that specifically works on secure authentication, thinks it has finally identified the missing piece of the puzzle. On Thursday, the organization published a white paper that lays out FIDO's vision for solving the usability issues that have dogged passwordless features and, seemingly, kept them from achieving broad adoption. FIDO's members collaborated to produce the paper, and they span chipmakers like Intel and Qualcomm, prominent platform developers like Amazon and Meta, financial institutions like American Express and Bank of America, and the developers of all major operating systems—Google, Microsoft, and Apple. The paper is conceptual, not technical, but after years of investment to integrate what are known as the FIDO2 and WebAuthn passwordless standards into Windows, Android, iOS, and more, everything is now riding on the success of this next step.' -- source: https://arstechnica.com/information-technology/2022/03/a-big-bet-to-kill-th… Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 (office) +64 (7) 577-5304 (home office) https://www.cs.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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Trickbot is using MikroTik routers to ply its trade. Now we know why
by Peter Reutemann 18 Mar '22

18 Mar '22

'For years, malicious hackers have been hacking large fleets of MikroTik routers and conscripting them into Trickbot, one of the Internet’s most destructive botnets. Now, Microsoft has finally figured out why and how the routers are being put to use. Trickbot came to light in 2016 as a trojan for stealing account passwords for use in bank fraud. Since then, Trickbot has mushroomed into one of the Internet's most aggressive threat platforms, thanks to its highly modular, multistage malware framework that provides a full suite of tools that are used to install ransomware and other forms of malware from other hacking groups. The malware driving Trickbot is notable for its advanced capabilities. It excels at gaining powerful administrator privileges, spreading rapidly from computer to computer in networks, and performing reconnaissance that identifies infected computers belonging to high-value targets. The malware often uses readily available software like Mimikatz or exploits like EternalBlue, which was stolen from the National Security Agency.' -- source: https://arstechnica.com/information-technology/2022/03/trickbot-is-using-mi… Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 (office) +64 (7) 577-5304 (home office) https://www.cs.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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Researcher uses Dirty Pipe exploit to fully root a Pixel 6 Pro and Samsung S22
by Peter Reutemann 17 Mar '22

17 Mar '22

'A researcher has successfully used the critical Dirty Pipe vulnerability in Linux to fully root two models of Android phones—a Pixel 6 Pro and Samsung S22—in a hack that demonstrates the power of exploiting the newly discovered OS flaw. The researcher chose those two handset models for a good reason: they are two of the few—if not the only—devices known to run Android version 5.10.43, the only release of Google's mobile OS that's vulnerable to Dirty Pipe. Because the LPE, or local privilege escalation, vulnerability wasn't introduced until the recently released version 5.8 of the Linux kernel, the universe of exploitable devices—whether mobile, Internet of Things, or servers and desktops—is relatively small.' -- source: https://arstechnica.com/information-technology/2022/03/researcher-uses-dirt… Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 (office) +64 (7) 577-5304 (home office) https://www.cs.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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Nasty Linux Netfilter Firewall Security Hole Found
by Peter Reutemann 16 Mar '22

16 Mar '22

'Sophos threat researcher Nick Gregory discovered a hole in Linux's netfilter firewall program that's "exploitable to achieve kernel code execution (via ROP [return-oriented programming]), giving full local privilege escalation, container escape, whatever you want." ZDNet reports: Behind almost all Linux firewalls tools such as iptables; its newer version, nftables; firewalld; and ufw, is netfilter, which controls access to and from Linux's network stack. It's an essential Linux security program, so when a security hole is found in it, it's a big deal. [...] This problem exists because netfilter doesn't handle its hardware offload feature correctly. A local, unprivileged attacker can use this to cause a denial-of-service (DoS), execute arbitrary code, and cause general mayhem. Adding insult to injury, this works even if the hardware being attacked doesn't have offload functionality! That's because, as Gregory wrote to a security list, "Despite being in code dealing with hardware offload, this is reachable when targeting network devices that don't have offload functionality (e.g. lo) as the bug is triggered before the rule creation fails." This vulnerability is present in the Linux kernel versions 5.4 through 5.6.10. It's listed as Common Vulnerabilities and Exposures (CVE-2022-25636), and with a Common Vulnerability Scoring System (CVSS) score of 7.8), this is a real badie. How bad? In its advisory, Red Hat said, "This flaw allows a local attacker with a user account on the system to gain access to out-of-bounds memory, leading to a system crash or a privilege escalation threat." So, yes, this is bad. Worse still, it affects recent major distribution releases such as Red Hat Enterprise Linux (RHEL) 8.x; Debian Bullseye; Ubuntu Linux, and SUSE Linux Enterprise 15.3. While the Linux kernel netfilter patch has been made, the patch isn't available yet in all distribution releases. ' -- source: https://linux.slashdot.org/story/22/03/15/221258 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 (office) +64 (7) 577-5304 (home office) https://www.cs.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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A brief tour of the PDP-11, the most influential minicomputer of all time
by Peter Reutemann 15 Mar '22

15 Mar '22

'The history of computing could arguably be divided into three eras: that of mainframes, minicomputers, and microcomputers. Minicomputers provided an important bridge between the first mainframes and the ubiquitous micros of today. This is the story of the PDP-11, the most influential and successful minicomputer ever. In their moment, minicomputers were used in a variety of applications. They served as communications controllers, instrument controllers, large system pre-processors, desk calculators, and real-time data acquisition handlers. But they also laid the foundation for significant hardware architecture advances and contributed greatly to modern operating systems, programming languages, and interactive computing as we know them today. In today’s world of computing, in which every computer runs some variant of Windows, Mac, or Linux, it’s hard to distinguish between the CPUs underneath the operating system. But there was a time when differences in CPU architecture were a big deal. The PDP-11 helps explain why that was the case. The PDP-11 was introduced in 1970, a time when most computing was done on expensive GE, CDC, and IBM mainframes that few people had access to. There were no laptops, desktops, or personal computers. Programming was done by only a few companies, mostly in assembly, COBOL, and FORTRAN. Input was done on punched cards, and programs ran in non-interactive batch runs.' -- source: https://arstechnica.com/gadgets/2022/03/a-brief-tour-of-the-pdp-11-the-most… Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 (office) +64 (7) 577-5304 (home office) https://www.cs.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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Researcher uses 379-year-old algorithm to crack crypto keys found in the wild
by Peter Reutemann 15 Mar '22

15 Mar '22

'Cryptographic keys generated with older software now owned by technology company Rambus are weak enough to be broken instantly using commodity hardware, a researcher reported on Monday. This revelation is part of an investigation that also uncovered a handful of weak keys in the wild. The software comes from a basic version of the SafeZone Crypto Libraries, which were developed by a company called Inside Secure and acquired by Rambus as part of its 2019 acquisition of Verimatrix, a Rambus representative said. That version was deprecated prior to the acquisition and is distinct from a FIPS-certified version that the company now sells under the Rambus FIPS Security Toolkit brand. Researcher Hanno Böck said that the vulnerable SafeZone library doesn't sufficiently randomize the two prime numbers it used to generate RSA keys. (These keys can be used to secure Web traffic, shells, and other online connections.) Instead, after the SafeZone tool selects one prime number, it chooses a prime in close proximity as the second one needed to form the key. "The problem is that both primes are too similar," Böck said in an interview. "So the difference between the two primes is really small." The SafeZone vulnerability is tracked as CVE-2022-26320. Cryptographers have long known that RSA keys that are generated with primes that are too close together can be trivially broken with Fermat's factorization method. French mathematician Pierre de Fermat first described this method in 1643.' -- source: https://arstechnica.com/information-technology/2022/03/researcher-uses-600-… Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 (office) +64 (7) 577-5304 (home office) https://www.cs.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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Intel Finds Bug In AMD's Spectre Mitigation, AMD Issues Fix
by Peter Reutemann 14 Mar '22

14 Mar '22

'"News of a fresh Spectre BHB vulnerability that only impacts Intel and Arm processors emerged this week," reports Tom's Hardware, "but Intel's research around these new attack vectors unearthed another issue. "One of the patches that AMD has used to fix the Spectre vulnerabilities has been broken since 2018." Intel's security team, STORM, found the issue with AMD's mitigation. In response, AMD has issued a security bulletin and updated its guidance to recommend using an alternative method to mitigate the Spectre vulnerabilities, thus repairing the issue anew.... Intel's research into AMD's Spectre fix begins in a roundabout way — Intel's processors were recently found to still be susceptible to Spectre v2-based attacks via a new Branch History Injection variant, this despite the company's use of the Enhanced Indirect Branch Restricted Speculation (eIBRS) and/or Retpoline mitigations that were thought to prevent further attacks. In need of a newer Spectre mitigation approach to patch the far-flung issue, Intel turned to studying alternative mitigation techniques. There are several other options, but all entail varying levels of performance tradeoffs. Intel says its ecosystem partners asked the company to consider using AMD's LFENCE/JMP technique. The "LFENCE/JMP" mitigation is a Retpoline alternative commonly referred to as "AMD's Retpoline." As a result of Intel's investigation, the company discovered that the mitigation AMD has used since 2018 to patch the Spectre vulnerabilities isn't sufficient — the chips are still vulnerable. The issue impacts nearly every modern AMD processor spanning almost the entire Ryzen family for desktop PCs and laptops (second-gen to current-gen) and the EPYC family of datacenter chips.... In response to the STORM team's discovery and paper, AMD issued a security bulletin (AMD-SB-1026) that states it isn't aware of any currently active exploits using the method described in the paper. AMD also instructs its customers to switch to using "one of the other published mitigations (V2-1 aka 'generic retpoline' or V2-4 aka 'IBRS')." The company also published updated Spectre mitigation guidance reflecting those changes [PDF].... AMD's security bulletin thanks Intel's STORM team by name and noted it engaged in the coordinated vulnerability disclosure, thus allowing AMD enough time to address the issue before making it known to the public. ' -- source: https://hardware.slashdot.org/story/22/03/13/200224 Cheers, Peter -- Peter Reutemann Dept. of Computer Science University of Waikato, NZ +64 (7) 858-5174 (office) +64 (7) 577-5304 (home office) https://www.cs.waikato.ac.nz/~fracpete/ http://www.data-mining.co.nz/

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