Risky Bulletin: Expired cards can be used for new transactions
Researchers show expired Visa contactless cards can be revived via NFC man-in-the-middle relay to run fraudulent transactions; roundup also covers major breaches.
University of Massachusetts Amherst researchers built an NFC man-in-the-middle rig that updates a card's expiration date in transit and relays the modified payment to POS terminals, reviving expired contactless cards; Visa terminals and the backends of all five banks studied failed to catch the manipulation. The same roundup reports Iranian hackers shut down a small UK power plant for four days, Lazarus breached South Korea's Presidential Office as part of a campaign exceeding 100 victims, and French telecom SFR suffered a breach affecting over 2.1 million customers.
Plug 'n' Pray: Agentic LLM-based Detection of Potential Log File Exposures in Third-Party Content Management System Plugins
Agentic LLM analysis validates 79 log file exposures across 62 of the 300 most-installed WordPress plugins, covering 250M+ active installations.
Researchers built an agentic LLM-based framework combining static and dynamic analysis to automatically detect insecure log files created by WordPress plugins. Scanning the 300 most-installed plugins, which account for roughly 75% of all active installations in the official ecosystem, it produced 81 findings with 79 manually reproduced across 62 plugins. Insufficiently secured log files can disclose credentials and personal data and have led to website compromises. The authors derive a taxonomy of log path and protection patterns and best practices, finding multi-layered protection often absent.
Your Shredded Visa Card May Still Work at the Checkout
UMass Amherst researchers demonstrated expired Visa contactless cards can complete real purchases via relay attacks exploiting Visa Kernel 3's unsigned expiry date handling.
University of Massachusetts Amherst researchers presented at USENIX Security 2026 that expired Visa contactless cards can be revived for real purchases through an NFC man-in-the-middle attack on Visa's Kernel 3. The attack alters the expiry date the terminal sees (tag 5F24) while leaving the Track 2 Equivalent Data (tag 57) sent to the issuing bank unchanged, and the card's cryptographic signature does not cover the expiry date. Two Android phones emulating card and terminal relayed transactions within Visa's 500-millisecond limit. Mastercard, American Express, and Discover kernels blocked the attack, while Visa Kernel 3 did not; researchers also modified the Consumer Device Cardholder Verification Method flag at five US banks, and attackers can also exploit Terminal Verification Results zero-filling. Visa was notified in May 2025 and December 2025; no CVE has been assigned.
Zombie Card Attack Can Revive Expired Visa Cards for Contactless Payments
UMass Amherst researchers demonstrate Zombie Card, an NFC relay attack that revives expired Visa contactless cards for in-store purchases without breaking cryptography.
Researchers at the University of Massachusetts Amherst presented the Zombie Card attack at USENIX Security 2026, showing that Visa's Kernel 3 does not cryptographically bind the Application Expiration Date (tag 5F24) the terminal reads with the Track 2 expiry seen by the issuer. By positioning an NFC man-in-the-middle relay, an attacker can rewrite the terminal-facing expiration date of an expired card and complete contactless purchases, provided the account remains open under the same PAN and the bank does not independently re-check expiry. Testing across five major US banks found three distinct policies; Visa Kernel 3 accepted the modified date, while Mastercard, American Express, and Discover kernels declined modified transactions. Findings were disclosed to Visa and affected banks in May 2025, no CVE has been assigned, and no exploitation has been reported.
Hackers Turn Windows Shadow Copies Into a Tool for Credential Theft and Ransomware
Attackers abuse Windows VSS shadow copies to delete recovery points before ransomware and to extract NTDS.dit/SAM credentials, demanding context-aware detection.
Threat actors are weaponizing the Volume Shadow Copy Service (VSS) for two purposes: destroying local recovery points via vssadmin.exe, wmic.exe, diskshadow.exe, wbadmin.exe, and bcdedit.exe before encryption, and accessing static copies of locked files such as NTDS.dit and SAM for credential theft. Ransomware families tied to shadow-copy removal include Akira, Black Basta, BlackCat, Conti, LockBit, Qilin, RansomHub, REvil, Ryuk, and WannaCry. Huntress's analysis of the Nightmare-Eclipse tool showed the BlueHammer technique chaining a Windows Defender timing issue with a VSS snapshot to dump the SAM database and decrypt NT hashes. Defenders should correlate VSS operations with parent process, hive access, and subsequent encryption activity, and maintain immutable off-host backups.
New DDRop Attack Breaks Intel TDX and AMD SEV-SNP Confidential Computing
DDRop uses a sub-$200 DDR5 interposer to drop memory writes, breaking Intel TDX and AMD SEV-SNP confidentiality guarantees.
Researchers at KU Leuven, ETH Zurich, Durham University, and Google will present DDRop at ACM CCS 2026, a first active interposer attack on DDR5 that silently drops memory writes so processors keep reading stale encrypted data, exploiting the missing freshness guarantee in Intel TDX, Intel Scalable SGX, and AMD SEV-SNP. On Intel TDX's default logical integrity mode it enabled reading victim VM memory, toggling debug mode, and forging remote attestation; AMD SEV-SNP was limited to copying pages between VMs. TDX's stronger cryptographic integrity blocks cross-VM attacks but likely not attestation forgery. The team will release board designs, firmware, and attack code on GitHub; no evidence of real-world use exists and no simple patch is available.
Hackers Steal Active Directory Password Hashes Without Attacking Domain Controllers Directly
Attackers use the DCSync technique to impersonate domain controllers and harvest AD password hashes and Kerberos keys without directly compromising domain controllers, Trellix warns.
Per Trellix, threat actors increasingly abuse Active Directory replication via DCSync, using privileged credentials to invoke DRSGetNCChanges and retrieve NTLM password hashes and Kerberos key material without running code on domain controllers. Capturing the krbtgt account hash enables forging Golden Tickets for persistent, highly privileged domain access. Because malicious replication traffic mimics legitimate DRS/RPC activity, defenders should monitor Windows Security Event ID 4662, restrict replication permissions, and investigate replication requests from non-domain-controller systems.
Researchers find a loophole that lets expired credit cards make unauthorized payments
UMass Amherst researchers showed at USENIX Security 2026 that NFC relay attacks can rewrite unprotected expiration dates, letting expired Visa contactless cards keep making payments.
UMass Amherst researchers presented the Zombie Card attack at USENIX Security 2026, using two smartphones to relay and modify NFC payment data from expired Visa cards. The expiration date lies outside the card's digital signature coverage in Visa Kernel 3, and one major US bank accepted $1-$500 test purchases plus live $2.79 and $3.19 purchases with rewritten dates. Mastercard, American Express, and Discover rejected tampered dates; researchers notified Visa in May 2025 and no CVE or confirmed fix existed at publication.
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.