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Re: Retrospective by 'gpg.fail' authors

GPG exploitation talk author clarifies a format-string 0day enabling code execution via printf %n writes and a polyglot PEM certificate payload.

Lexi Groves, author of the gpg.fail talk, clarified on oss-security that the first finding was an actual zero-day: a classic printf injection using %n for memory writes, with multiple X.509 certificates in one PEM file to re-enter and defeat ASLR before calling execv@plt. The payload executed the certificate itself, a polyglot file made by inserting a shebang and bash command into the PEM. A second finding was hash-collided by another party before the author could exploit it.

oss-securityupdated · 8h agofirst · 12h agoResearch 6 sources

Almost Half of Malware Samples Communicate Direct to IP

Unit 42 analysis of 4 million malware reports finds 45% of C2-active samples connect directly to hard-coded IPs, bypassing DNS defenses.

Palo Alto Unit 42 analyzed over 4 million Advanced WildFire dynamic analysis reports and found that 45.32% of malware samples with C2 activity made at least one direct-to-IP connection, accounting for 23.17% of all C2 connection attempts. The firm proposes zero trust IP (ZT-IP), an enforcement approach that verifies whether outbound destinations were ever sanctioned by a DNS response. ZT-IP analysis surfaced Phorpiex ransomware droppers fetching payloads directly from C2 IPs, a persistent data exfiltration campaign using an obfuscated \GET protocol, and Mozi P2P botnet payloads delivered to IoT devices without DNS. Only 1% of benign samples connected directly to untrusted IP addresses.

Palo Alto Unit 42 · Aug 17, 2026Research

The Gopher in the Room: Analysis of GoLang Malware in the Wild

Unit 42 analysis of 10,700 Go-compiled malware samples shows steady growth in the wild, with 92% targeting Windows and top families including Veil, GoBot2, and HERCULES.

Unit 42 collected roughly 10,700 unique Go-compiled malware samples and found that Go usage by malware developers has steadily risen in recent months. About 92% of samples targeted Windows and 75% were attributed to known families, led by Veil, GoBot2, and HERCULES. The most prevalent groupings were penetration testing tools, remote access Trojans, and backdoors. Statically linked Go binaries average 4.65MB, which can complicate phishing delivery but sometimes causes antivirus products to skip or fail scanning.

Palo Alto Unit 42 · Aug 17, 2026Research1

Unmasking Cloud Identities: From Behavioral Clustering to Automated Detection

Unit 42 clusters behavior of 40,000+ AWS identities from 125 cloud environments to map functional roles and enable lightweight SQL-based detection.

Palo Alto Unit 42 built an unsupervised behavioral clustering model using UMAP and HDBSCAN on AWS CloudTrail logs to map cloud identities to functional roles such as administrators, backup services, security tooling and DevOps. The study analyzed over 40,000 identities across 125 cloud environments over two months. The researchers show that heuristics extracted from the clustering map can be implemented in standard SQL, enabling role classification at scale without running a continuous ML pipeline. The methodology extends to audit logs from other cloud providers, SaaS and Kubernetes.

Palo Alto Unit 42 · 2d agoResearch

Understanding Angler Exploit Kit

Unit 42 explains exploit kit fundamentals, describing how landing pages profile victims, deliver exploits, and install malware payloads on Windows hosts.

Unit 42 published a primer on exploit kit fundamentals, defining vulnerabilities, exploits, malware payloads, actors, and campaigns in EK-based attacks. It explains the infection chain: a landing page profiles the victim's Windows system for vulnerable applications such as Flash Player, Java, Silverlight, and Internet Explorer, then a matching exploit executes a downloader or final payload, often delivered encrypted with XOR or RC4. The post also describes the EK-as-a-Service business model, in which leading EKs are rented for a few thousand dollars per month while buyers supply campaign infrastructure.

Palo Alto Unit 42 · Aug 17, 2026Research

AD Rights Management Service (Part 2): Extraction, Offline Decryption, and the Unrotatable Key

Huntress research shows AD RMS SLC root key is unrotatable and never expires, so its compromise permanently exposes all RMS-protected documents.

Part 2 of Huntress's AD RMS series details server-side attacks: extracting the Server Licensor Certificate (SLC) private key and performing offline decryption of protected documents. The SLC key has no expiry or rotation mechanism, with a 255-year certificate validity (2002–2258), so whoever recovers it can decrypt every document the deployment ever protected, indefinitely. The author released SharpRMS, a unified tool combining the 2016 DisARMS client-side attacks with new server-side key extraction and decryption capabilities. The research frames the SLC as comparable to KRBTGT and the DPAPI domain backup key, though not equivalent to domain compromise.

Huntress · 6d agoResearch