This Week in Security

261 Articles

This Week In Security: Lingering Spectre, Deep Fakes, And CoreAudio

May 16, 2025 by 4 Comments

Spectre lives. We’ve got two separate pieces of research, each finding new processor primitives that allow Spectre-style memory leaks. Before we dive into the details of the new techniques, let’s quickly remind ourselves what Spectre is. Modern CPUs use a variety of clever tricks to execute code faster, and one of the stumbling blocks is memory latency. When a program reaches a branch in execution, the program will proceed in one of two possible directions, and it’s often a value from memory that determines which branch is taken. Rather than wait for the memory to be fetched, modern CPUs will predict which branch execution will take, and speculatively execute the code down that branch. Once the memory is fetched and the branch is properly evaluated, the speculatively executed code is rewound if the guess was wrong, or made authoritative if the guess was correct. Spectre is the realization that incorrect branch prediction can change the contents of the CPU cache, and those changes can be detected through cache timing measurements. The end result is that arbitrary system memory can be leaked from a low privileged or even sandboxed user process.

In response to Spectre, OS developers and CPU designers have added domain isolation protections, that prevent branch prediction poisoning in an attack process from affecting the branch prediction in the kernel or another process. Training Solo is the clever idea from VUSec that branch prediction poisoning could just be done from within the kernel space, and avoid any domain switching at all. That can be done through cBPF, the classic Berkeley Packet Filter (BPF) kernel VM. By default, all users on a Linux system can run cBPF code, throwing the doors back open for Spectre shenanigans. There’s also an address collision attack where an unrelated branch can be used to train a target branch. Researchers also discovered a pair of CVEs in Intel’s CPUs, where prediction training was broken in specific cases, allowing for a wild 17 kB/sec memory leak.

Continue reading “This Week In Security: Lingering Spectre, Deep Fakes, And CoreAudio” →

This Week In Security: Encrypted Messaging, NSO’s Judgement, And AI CVE DDoS

May 9, 2025 by 3 Comments

Cryptographic messaging has been in the news a lot recently. Like the formal audit of WhatsApp (the actual PDF). And the results are good. There are some minor potential problems that the audit highlights, but they are of questionable real-world impact. The most consequential is how easy it is to add additional members to a group chat. Or to put it another way, there are no cryptographic guarantees associated with adding a new user to a group.

The good news is that WhatsApp groups don’t allow new members to read previous messages. So a user getting added to a group doesn’t reveal historic messages. But a user added without being noticed can snoop on future messages. There’s an obvious question, as to how this is a weakness. Isn’t it redundant, since anyone with the permission to add someone to a group, can already read the messages from that group?

That’s where the lack of cryptography comes in. To put it simply, the WhatsApp servers could add users to groups, even if none of the existing users actually requested the addition. It’s not a vulnerability per se, but definitely a design choice to keep in mind. Keep an eye on the members in your groups, just in case. Continue reading “This Week In Security: Encrypted Messaging, NSO’s Judgement, And AI CVE DDoS” →

This Week In Security: AirBorne, EvilNotify, And Revoked RDP

May 2, 2025 by 2 Comments

This week, Oligo has announced the AirBorne series of vulnerabilities in the Apple Airdrop protocol and SDK. This is a particularly serious set of issues, and notably affects MacOS desktops and laptops, the iOS and iPadOS mobile devices, and many IoT devices that use the Apple SDK to provide AirPlay support. It’s a group of 16 CVEs based on 23 total reported issues, with the ramifications ranging from an authentication bypass, to local file reads, all the way to Remote Code Execution (RCE).

AirPlay is a WiFi based peer-to-peer protocol, used to share or stream media between devices. It uses port 7000, and a custom protocol that has elements of both HTTP and RTSP. This scheme makes heavy use of property lists (“plists”) for transferring serialized information. And as we well know, serialization and data parsing interfaces are great places to look for vulnerabilities. Oligo provides an example, where a plist is expected to contain a dictionary object, but was actually constructed with a simple string. De-serializing that plist results in a malformed dictionary, and attempting to access it will crash the process.

Another demo is using AirPlay to achieve an arbitrary memory write against a MacOS device. Because it’s such a powerful primative, this can be used for zero-click exploitation, though the actual demo uses the music app, and launches with a user click. Prior to the patch, this affected any MacOS device with AirPlay enabled, and set to either “Anyone on the same network” or “Everyone”. Because of the zero-click nature, this could be made into a wormable exploit. Continue reading “This Week In Security: AirBorne, EvilNotify, And Revoked RDP” →

This Week In Security: XRP Poisoned, MCP Bypassed, And More

April 25, 2025 by 7 Comments

Researchers at Aikido run the Aikido Intel system, an LLM security monitor that ingests the feeds from public package repositories, and looks for anything unusual. In this case, the unusual activity was five rapid-fire releases of the xrpl package on NPM. That package is the XRP Ledger SDK from Ripple, used to manage keys and build crypto wallets. While quick point releases happen to the best of developers, these were odd, in that there were no matching releases in the source GitHub repository. What changed in the first of those fresh releases?

The most obvious change is the checkValidityOfSeed() function added to index.ts. That function takes a string, and sends a request to a rather odd URL, using the supplied string as the ad-referral header for the HTML request. The name of the function is intended to blend in, but knowing that the string parameter is sent to a remote web server is terrifying. The seed is usually the root of trust for an individual’s cryptocurrency wallet. Looking at the actual usage of the function confirms, that this code is stealing credentials and keys.

The releases were made by a Ripple developer’s account. It’s not clear exactly how the attack happened, though credential compromise of some sort is the most likely explanation. Each of those five releases added another bit of malicious code, demonstrating that there was someone with hands on keyboard, watching what data was coming in.

The good news is that the malicious releases only managed a total of 452 downloads for the few hours they were available. A legitimate update to the library, version 4.2.5, has been released. If you’re one of the unfortunate 452 downloads, it’s time to do an audit, and rotate the possibly affected keys. Continue reading “This Week In Security: XRP Poisoned, MCP Bypassed, And More” →

This Week In Security: No More CVEs, 4chan, And Recall Returns

April 18, 2025 by 7 Comments

The sky is falling. Or more specifically, it was about to fall, according to the security community this week. The MITRE Corporation came within a hair’s breadth of running out of its contract to maintain the CVE database. And admittedly, it would be a bad thing if we suddenly lost updates to the central CVE database. What’s particularly interesting is how we knew about this possibility at all. An April 15 letter sent to the CVE board warned that the specific contract that funds MITRE’s CVE and CWE work was due to expire on the 16th. This was not an official release, and it’s not clear exactly how this document was leaked.

Many people made political hay out of the apparent imminent carnage. And while there’s always an element of political maneuvering when it comes to contract renewal, it’s worth noting that it’s not unheard of for MITRE’s CVE funding to go down to the wire like this. We don’t know how many times we’ve been in this position in years past. Regardless, MITRE has spun out another non-profit, The CVE Foundation, specifically to see to the continuation of the CVE database. And at the last possible moment, CISA has announced that it has invoked an option in the existing contract, funding MITRE’s CVE work for another 11 months.

Continue reading “This Week In Security: No More CVEs, 4chan, And Recall Returns” →

This Week In Security: AI Spam, SAP, And Ivanti

April 11, 2025 by 13 Comments

AI continues to be used in new and exciting ways… like generating spam messages. Yes, it was inevitable, but we now have spammers using LLM to generate unique messages that don’t register as spam. AkiraBot is a Python-powered tool, designed to evade CAPTCHAs, and post sketchy SEO advertisements to web forms and chat boxes around the Internet.

AkiraBot uses a bunch of techniques to look like a legitimate browser, trying to avoid triggering CAPTCHAs. It also runs traffic through a SmartProxy service to spread the apparent source IP around. Some captured logs indicate that of over 400,000 attempted victim sites, 80,000 have successfully been spammed.

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This Week In Security: Target Coinbase, Leaking Call Records, And Microsoft Hotpatching

April 4, 2025 by 2 Comments

We know a bit more about the GitHub Actions supply chain attack from last month. Palo Alto’s Unit 42 has been leading the charge on untangling this attack, and they’ve just released an update to their coverage. The conclusion is that Coinbase was the initial target of the attack, with the open source agentkit package first (unsuccessfully) attacked. This attack chain started with pull_request_target in the spotbugs/sonar-findbugs repository.

The pull_request_target hook is exceptionally useful in dealing with pull requests for a GitHub repository. The workflow here is that the project defines a set of Continuous Integration (CI) tests in the repository, and when someone opens a new Pull Request (PR), those CI tests run automatically. Now there’s an obvious potential problem, and Github thought of it and fixed it a long time ago. The GitHub Actions are defined right in the repository, and letting any pull request run arbitrary actions is a recipe for disaster. So GitHub always uses actions as they are defined in the repository itself, ignoring any incoming changes in the PR. So pull_request_target is safe now, right? Yes, with some really big caveats.

The simplest security problem is that many projects have build scripts in the repository, and those are not considered part of GitHub Actions by GitHub. So include malicious code in such a build script, make it a PR that runs automatically, and you have access to internal elements like organization and repository secrets and access tokens. The most effective mitigation against this is to require approval before running workflows on incoming PRs.

So back to the story. The spotbugs/sonar-findbugs repository had this vulnerability, and an attacker used it to export secrets from a GitHub Actions run. One of those secrets happened to be a Personal Access Token (PAT) belonging to a spotbugs maintainer. That PAT was used to invite a throwaway account, [jurkaofavak], into the main spotbugs repository. Two minutes after being added, the [jurkaofavak] account created a new branch in spotbugs/spotbugs, and deleted it about a second later. This branch triggered yet another malicious CI run, now with arbitrary Github Actions access rather than just access through a build script. This run leaked yet another Personal Access Token, belonging to a maintainer that worked on both the spotbugs and reviewdog projects. Continue reading “This Week In Security: Target Coinbase, Leaking Call Records, And Microsoft Hotpatching” →