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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.

Security Affairs · 26d agoResearch

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.

Help Net Security · 28d agoResearch

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.

The Hacker News · 27d agoResearch

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.

Risky Business News · 23d agoResearch1

A battery storage cyberattack would look exactly like a badly tuned controller

Risk modeling suggests a few hundred compromised grid-scale batteries dispatched through cloud optimizers could trigger blackouts in Texas or Great Britain.

Centrii analysis estimates 1,500 compromised one-megawatt units (5.4% of ERCOT's ~28 GW fleet) or 400 units (about 29% of Great Britain's ~1,400-unit fleet) could destabilize the grids, with modeled damage of $12-65 billion in Texas and a national blackout costing £2-10 billion in Britain. The study puts the probability of a major attack affecting at least one million people by 2031 at 92.1%, dropping to 61.4% with IEC 62443 certification and quarterly drills, based on 10,000 Monte Carlo runs. Because hostile battery swings are phased like legitimate frequency response, control rooms would see nothing unusual; Centrii proposes hunting for a reverse-governor signature where inverter output feeds oscillations. Spain's April 2025 blackout took an expert panel until March 2026 to rule out cyberattack, partly because key plants had no recordings.

Help Net Security · 15d agoResearch

Are Unreachable Nodes Truly Safe? Fully Eclipsing Monero's P2P Network!

Researchers present Nyx and Moros, the first eclipse attacks against Monero nodes behind NATs, requiring no inbound access and demonstrated on mainnet.

The paper presents the first eclipse attacks tailored to unreachable Monero nodes operating behind NATs, requiring no inbound access to the victim. The attacks poison the peerlists of reachable nodes, which relay contamination to unreachable nodes' whitelists, then exploit Monero's outbound connection refresh logic to evict benign neighbors and monopolize all outbound connections. Nyx achieves a complete, persistent eclipse of long-running unreachable nodes in large-scale SEED Emulator simulations, while Moros stealthily eclipses newly joined nodes during bootstrapping and was demonstrated on the Monero mainnet. Countermeasures are proposed.

arXiv cs.CR · 7d agoResearch

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

Your Expired Visa Card Could Be ‘Zombified’ to Make Contactless Payments

Roundup: expired Visa cards can be revived for contactless payments via NFC relay; plus Apple spyware warnings and Ukraine cyberattacks on Russian e-commerce.

WIRED's weekly security roundup leads with research showing expired Visa contactless cards can be revived to make new payments through an NFC man-in-the-middle attack that alters the card's expiration date. The roundup also covers Apple sending an unprecedented volume of spyware warnings to users and Ukrainian cyber and drone attacks against a major Russian e-commerce company.

WIRED · Security · 25d agoResearch

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