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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

Apple Xcode Integer Underflow Flaw Lets Crafted Archives Leak Memory and Crash Builds

Researchers disclosed an integer underflow in Apple's Mach-O archive parser that lets crafted static libraries crash Xcode builds or leak process memory.

SecureLayer7 disclosed an integer underflow in the mach_o::Archive::Entry::name() function in Apple's open-source dyld project, reported to Apple Product Security on May 23, 2026, with no public patch after more than 90 days. Crafted static archives (.a files) cause the parser's unsigned index to wrap to SIZE_MAX, producing SIGSEGV crashes in the ld-prime linker, out-of-bounds reads that may print adjacent memory to stderr, or SIGABRT in libtool and ranlib. The modern parser is used by ld-prime, the default linker for arm64, arm64e, and x86_64 since Xcode 15, while legacy ld-classic is unaffected. Crafted archives need only be processed, creating supply-chain risk via vendored SDKs, binary dependencies, and CI pipelines.

GBHackers · 6d agoVulnerability1

Homebrew 7.0.0 is out, here’s what changed for security

Homebrew 7.0.0 closes eight security advisories, including a High sudo execution bug fixed in 6.0.12, and ships brew vulns vulnerability scanning.

Homebrew 7.0.0 closes eight security advisories rated one High, two Moderate, and five Low. The High flaw let unsigned cask removal metadata execute commands with sudo (fixed in 6.0.12), while the 7.0.0 Moderate closes a LaunchServices escape that let a malicious cask execute code outside the macOS install sandbox. The release ships brew vulns, which checks installed formulae against OSV.dev, extends build attestation verification to third-party tap bottles, and replaces Bubblewrap with Landlock sandboxing on Linux.

Help Net Security · 1d agoVulnerability

Stately Taurus Activity in Southeast Asia Links to Bookworm Malware

Unit 42 links Stately Taurus APT activity in ASEAN region and Myanmar to the decade-old Bookworm malware family via infrastructure overlaps.

Unit 42 connected Stately Taurus (aka Mustang Panda) espionage activity targeting ASEAN-affiliated organizations and Myanmar to the Bookworm malware family, first published in 2015. Earlier attacks delivered the PubLoad stager via DLL sideloading, with a PubLoad variant communicating with C2 at 123.253.32[.]15 while mimicking Windows Update URLs. Three previously unreported loader samples from 2021-2022 used UUID-decoded shellcode loaded via heap allocation and API callbacks, ultimately decrypting and loading Bookworm DLLs. A ToneShell backdoor variant shared debug paths with Bookworm loaders, and the January 2024 CSIRT CTI post corroborated the Myanmar attacks.

Palo Alto Unit 42 · Aug 17, 2026Threat actor in the wild

Hackers Weaponize AI Safety Guardrails to Hide Malware From LLM-Powered Security Scanners

ESET says Russia-aligned actor UAC-0099 hid guardrail-triggering comments in VBScript to derail LLM-based malware scanners in Ukraine.

ESET researchers linked a technique named GuardBreaker to Russia-aligned threat actor UAC-0099 during an attack against an organization in Ukraine. The group embedded a safety-sensitive, weapon-related request in a VBScript comment so an LLM-powered analysis tool might interpret it as an instruction and refuse or truncate analysis before reaching the malicious code. The VBScript downloaded MATCHBOIL, a C#-based loader used by the group alongside MATCHWOK and DRAGSTARE. OWASP guidance recommends treating code comments and metadata as untrusted input, sanitizing it, and never treating an LLM refusal as a clean verdict.

GBHackersupdated · 4d agofirst · 5d agoThreat actor in the wild 3 sources1