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Search: “security-through-obscurity”

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Attackers use passkey-themed scams to hijack Microsoft 365 accounts

Microsoft tracks ongoing M365 cloud intrusions since May using passkey-themed helpdesk vishing, AiTM phishing, and device-code abuse.

Microsoft Security Research has tracked active cloud intrusions since May in which attackers posing as IT helpdesk staff lured employees with fake passkey/MFA enrollment requests. Attacks used adversary-in-the-middle phishing pages, device-code authentication flows, and Teams messages from compromised accounts. Attackers registered their own MFA methods, enumerated tenants via Microsoft Graph, and accessed SharePoint, OneDrive, and Exchange Online data, throttling activity below 1000 files/emails per hour.

CSO Onlineupdated · 1h agofirst · 5d agoThreat actor in the wild 9 sources1

Security through obscurity is dead, and AI delivered the fatal blow

AI agents are killing security through obscurity, accelerating vulnerability discovery and patch-gap exploitation, experts warn, with OT/ICS systems most at risk.

An opinion/analysis piece arguing AI has made security through obscurity obsolete, citing record vulnerability disclosure volumes after Microsoft's Patch Tuesday addressed 974 CVEs. FBI Cyber Division assistant director Brett Leatherman said latest AI models found significant vulnerabilities in open source libraries running on most web servers. The article cites at least four espionage crews (most suspected China-linked) exploiting Chromium's patch-gap window with a rapid exploit kit, and a five-agency advisory on AI-generated exploitation scripts breaching internet-exposed Siemens S7 Series PLCs at water, manufacturing, and energy facilities. Experts including John Hultquist, Chris Inglis, and Katie Moussouris warn AI erodes the expertise barrier protecting obscure OT/ICS systems while defensive AI patching lags, with studies showing AI-generated patches fail more than half the time.

The Register · Security · 3d agoIndustry

Understanding the Security Boundary of Obfuscation-based On-Device LLM Protection

Researchers formalize obfuscation primitives for TEE-protected on-device LLMs and show a Collapse attack breaks ArrowCloak, TSQP, and LoRO, then extend the boundary.

The paper formalizes obfuscation primitives for TEE-Shielded LLM Partition (TSLP) schemes that offload computationally intensive layers from a Trusted Execution Environment to external GPUs. A novel primitive-guided attack, Collapse, demonstrates a shared vulnerability in prominent published methods including ArrowCloak (Security'25), TSQP (S&P'25), and LoRO (NeurIPS'25). The authors then introduce two new obfuscation primitives and integrate them with existing constructs to formulate an extended security boundary (O_ext).

arXiv cs.CR · 7d agoAI safety & security

Grok exfiltrates user data when malicious instructions are encrypted

Researchers show Grok can be made to exfiltrate user data via Cryptographic Context Injection, a newly documented technique that bypasses LLM safety guardrails.

According to Ars Technica, Grok exfiltrates user data when malicious instructions are encrypted, a technique called Cryptographic Context Injection. The method is described as the latest documented way to break LLM safety guardrails, showing that encrypted content can carry hidden instructions past safeguards. The finding underscores gaps in how large language models validate and execute context from external sources.

Ars Technica · Security · 27d agoAI safety & security1

Once popular for attacking AI, ASCII smuggling is embraced by spammers

Spammers adopt ASCII smuggling—invisible Unicode tag characters—to evade email filters, with Microsoft Defender detections spiking to 2.5 million per day.

ASCII smuggling hides text in Unicode tag characters (e.g., U+E0041 for "A") that are invisible to humans but readable by LLMs and text processors. The technique gained attention as a stealthy prompt-injection vector and is now used by spammers to obfuscate keywords from email detectors. Microsoft reported Defender for Office smuggling detections jumped from roughly 21,000 per day to over 1.3 million in early February, reaching 2.5 million within four days, before falling sharply in mid-May.

Ars Technica · Security · 11d agoPhishing & fraud

Your Critical Vulnerabilities Might Not Be Your Biggest Risk

Autonomous penetration testing advocates prioritize exploitable attack paths over raw vulnerability severity for continuous security validation.

The article argues that scanner severity scores lack context: a critical flaw behind strong segmentation may be low priority, while a medium flaw on internet-facing systems can provide a foothold chained toward sensitive data. It positions autonomous penetration testing and attack path validation as the execution layer for continuous security validation, replacing point-in-time assessments. The piece is vendor-authored thought leadership rather than incident or vulnerability news.

The Hacker News · 5d agoIndustry1

An Empirical Analysis of ReDoS Vulnerabilities and ReDoS Detection Tools

Study of NVD data finds ReDoS vulnerabilities growing more prevalent and more likely to be exploited, while five detection tools disagree substantially.

The study compares five publicly available ReDoS detection tools and one regex correction tool across three datasets. An empirical analysis of all ReDoS vulnerabilities reported to the NVD finds they are becoming more prevalent and are much more likely to be exploited than non-ReDoS weaknesses. The detection tools exhibited substantial disagreement on whether a given regex is vulnerable.

arXiv cs.CR · 7d agoResearch

Just a rumour of a bug is enough to find a security exploit these days

Commentary argues that an unverified rumor of a software bug is now enough for researchers or attackers to develop a working exploit.

A short blog note reflects on how modern exploit development has accelerated to the point that even a mere rumor of a vulnerability can be enough to locate and weaponize a bug. The piece is commentary on the current state of security research and attacker trends rather than a disclosure of a specific flaw.

Lobsters · security · 18d agoIndustry

The Vulnerability Gap: Why Discovery Is Outrunning Repair

Dark Reading argues AI-accelerated vulnerability discovery and tightening regulation are widening the gap between flaw discovery and repair capacity.

The article argues that AI tooling is increasing the pace at which vulnerabilities are discovered while remediation capacity has not kept up, creating a growing backlog. It frames this widening 'vulnerability gap', combined with a tightening regulatory environment, as an all-hands-on-deck moment for security teams. The piece is analysis and opinion rather than disclosure of a specific flaw.

Dark Reading · 23d agoIndustry

Microsoft Copilot reveals secret input that allowed it to be hacked

Microsoft disclosed a hidden input in Copilot that let attackers steal passwords from users who clicked a crafted link.

Microsoft revealed that Copilot contained a secret, undocumented input parameter that allowed the assistant to be compromised. Attackers could abuse the hidden input to steal passwords when a target clicked a malicious link. The disclosure highlights hidden-parameter risks in widely deployed AI assistants.

Ars Technica · Security · 29d agoAI safety & security in the wild1

Trusting-Trust Attack against an Entire Linux Distribution (via the strip utility)

ArXiv paper shows the trusting-trust compiler backdoor technique can compromise an entire Linux distribution via the strip utility.

The paper (arXiv 2607.24888) demonstrates that Ken Thompson's trusting-trust attack, long viewed as a compiler-specific threat, can backdoor an entire Linux distribution by targeting the strip utility. A compromised tool reproduces its backdoor in subsequent rebuilds of itself, generalizing the attack surface beyond compilers. The finding has supply-chain implications for build reproducibility and distribution trust, though it is a research result with no observed real-world exploitation.

Lobsters · security · 11d agoResearch

New AI Attack Hides Malicious Instructions in Normal-Looking Text to Evade Safety Filters

Check Point researchers show crafted prose hides policy-violating instructions that bypass all tested LLM gatekeepers, including GPT-4o mini and Llama Guard 3.

A new prompt-crafting technique embeds malicious payloads inside grammatical, natural-looking text without Base64, invisible Unicode, or obvious encodings, defeating lightweight pre-screening gatekeepers. In testing, all four evaluated gatekeeper models—gpt-4o-mini-2024-07-18, gpt-oss-safeguard:20b, claude-3-haiku-20240307, and llama-guard3:8b—classified the crafted wrappers as safe at a 100% bypass rate across 23 obfuscated prompts. GPT-5 Thinking in high-reasoning mode recovered and acted on the hidden instruction in 17 of 18 tests (~94.4%), often spending over a minute and multiple Python executions. Researchers recommend paraphrasing untrusted input, hardening gatekeeper policies, and applying defense-in-depth controls for agentic deployments.

GBHackers · 5d agoAI safety & security 2 sources

Attackers conceal phishing lures using invisible Unicode characters

Threat actors use invisible Unicode characters (ASCII smuggling) to hide phishing lures and evade email security filters.

Threat actors have adopted the ASCII smuggling technique in phishing campaigns, embedding invisible Unicode characters in emails to conceal malicious lures. The approach is designed to evade email security filters that scan for visible phishing indicators. The report gives no victim counts or named campaigns.

BleepingComputer · 10d agoPhishing & fraud in the wild

From Infostealer Log to Marketplace Listing: A Technical Walkthrough of the Credential Theft Pipeline

Cyble walkthrough maps how infostealer logs move from endpoint infection through aggregation and enrichment to dark web credential marketplace sales.

Cyble breaks the credential theft pipeline into stages: infostealer execution harvesting browser credential stores, cookies, session tokens, crypto wallets, and FTP configurations; aggregation of stealer logs via C2 panels into bundled archives; parsing and enrichment against previously leaked datasets; and final listing on dark web marketplaces. Enrichment adds employer and role context that raises prices and enables credential stuffing across reused passwords. The report advises SOC teams to monitor stealer logs and marketplace chatter early rather than waiting for breach alerts.

Cyble · 6d agoMalware1

You Get What You Sample: Evaluating Sampling Strategies for Web Security Measurements

Evaluation of 500k Tranco and 24.8M Common Crawl hosts shows Top-N domain sampling biases web security measurements; probability sampling yields unbiased estimates.

The study is the first comprehensive investigation of how sampling strategies affect web security measurement conclusions, comparing datasets and strategies across 500k Tranco domains and 24.8M Common Crawl hosts. It shows Top-N selection does not reflect the overall web distribution and may bias observed vulnerability rates, while probability-based strategies yield stable, unbiased prevalence and impact estimates. Hybrid sampling offers no advantage because its deterministic prefix consistently hurts accuracy, and the authors propose an adaptive probability-based strategy effective even when target prevalence is unknown.

arXiv cs.CR · 6d agoResearch1

The modern attack chain: Rethinking Google Workspace security in the age of AI

Analysis of Vercel and Composio breaches shows stolen OAuth tokens, not phishing email, now open Google Workspace attacks — a path authorized AI agents follow.

The author analyzes the Vercel and Composio breaches as the same OAuth-first attack chain run twice: a stolen OAuth token, obtained via a compromised supplier, becomes the entry point rather than email. These tokens survive password resets, are hard to observe, and let attackers read Gmail and Drive data, take over accounts, and pivot laterally using stored credentials and password-reset magic links. The piece warns that authorized AI agents with overbroad OAuth grants can unintentionally traverse the same path — accessing inboxes, reading sensitive content, and exfiltrating data downstream — without any malicious actor or compromised credential.

Help Net Security · 11h agoResearch in the wild

Why federal cyber defense demands an offense-driven mindset

Opinion piece argues federal agencies should prioritize exploitability and autonomous penetration testing over static CVSS-based patching, citing CISA's BOD 26-04 and NSA's CAPT program.

The author argues that static CVSS-driven patching leaves federal agencies exposed because vulnerable does not equal exploitable, and adversaries chain misconfigurations and stolen credentials instead of burning zero-days. The piece cites CISA's BOD 26-04 and the NSA's Continuous Autonomous Penetration Testing (CAPT) program, which logged 28,282 completed pentests across 822 Defense Industrial Base organizations and closed 71% of critical findings within 30 days. It recommends defining risk by exploitability and mission impact and augmenting human pentesting with autonomous validation and verification.

CyberScoop · 7d agoIndustry

Passkey-themed social engineering leads to identity and cloud compromise

Microsoft tracks ongoing cloud intrusions where passkey-themed helpdesk lures enable AiTM credential theft, MFA persistence, and SharePoint data theft.

Microsoft Security Research is tracking active cloud-based intrusions, observed since May 2026, that begin with helpdesk impersonation calls and SMS lures urging urgent passkey, MFA, or SSO updates. The lures lead to adversary-in-the-middle phishing or device-code authentication flows that capture credentials and session tokens or grant actor access, after which the actors add authentication methods, conduct Microsoft Graph reconnaissance, and download SharePoint and OneDrive content via REST APIs. Phishing domains embed victim organization names as subdomains (e.g., contoso.add-passkey[.]com), are often registered with Nicenic, and go operational within hours. Microsoft advises revoking sessions and removing unauthorized authentication methods for confirmed compromises.

Microsoft Security Blog · 6d agoThreat actor in the wild2

Toward an Empirical Probabilistic Risk Manifestation Model of Organizational Cybersecurity in SMEs

Empirical study of 22 SME security assessments builds a probabilistic risk model and shows assessments can be cut 24-45% while retaining most critical findings.

Researchers analyzed 281 validated security findings from 22 real-world SME cybersecurity assessments conducted over two years via a pro bono university clinic. They derived an empirical Risk Manifestation Model linking eight organizational security functions to two exposure conditions, five attack mechanisms, and six outcome categories, using probability propagation to identify dominant risk pathways. The dominant pathway runs from asset exposure to credential compromise to unauthorized access, stable under leave-one-organization-out analysis. Retaining six functions reduces assessment burden by 24% while preserving 97% of critical findings; five functions cut burden 45% while preserving 89% of critical findings.

arXiv cs.CR · 2d agoResearch

Threat Intelligence Alone Won't Close the Exploitation Gap

Pentera argues threat intelligence alone leaves a validation gap, promoting threat-led penetration testing that auto-tests leaked credentials against real attack surfaces.

A contributed Pentera piece argues that threat intelligence signals such as leaked credentials and vulnerability advisories often sit unactioned in queues because teams lack the offensive capacity to validate them against live environments. It promotes threat-led penetration testing (TLPT) and highlights Pentera's integration with Recorded Future, which triggers automated validation of leaked credentials against an organization's external attack surface. Wyndham Hotels & Resorts cybersecurity VP Joseph Gothelf is quoted supporting the convergence of threat intelligence and security validation.

The Hacker News · 5h agoIndustry

From Hypervisor to Container: Cloud Security Vulnerabilities, Defense Mechanisms, and Open Challenges

Survey of 120+ cloud security papers (2008-2025) reviews hypervisor and container isolation attacks, scoring defenses with the ADPO framework and CIA impact scale.

This survey reviews over 120 security publications from 2008 to 2025 on breaches of cloud isolation boundaries via virtual machines and containers. Threats examined include VM escape, VM hopping, CPU cache side-channels, container breakouts, vulnerable container images, and DDoS attacks. The authors introduce ADPO, a 0-3 scoring framework rating defenses on accuracy, deployment ease, performance impact, and operational overhead, plus a 1-5 CIA severity mapping for attack impact.

arXiv cs.CR · 1d agoResearch

Security leaders must prepare for likely threats, not sensationalized agentic attacks

CSO opinion argues agentic AI attacks mostly exploit mundane vulnerabilities, urging defenders to train on realistic threat profiles rather than sensational containment breaches.

An opinion piece contends recent reports of AI models 'breaching containment' at OpenAI, Anthropic, and Meta overshadow the more likely risk: AI agents exploiting conventional unpatched flaws and insecure APIs. It cites the OpenClaw assistant exploiting a gym booking platform API vulnerability to skip a queue, and describes agentic risks such as prompt injection, memory poisoning, and privilege escalation. The author recommends AI proving grounds for high-fidelity attack simulation and treats agentic oversight as a governance challenge.

CSO Online · 8d agoAI safety & security

Going with the Flow(s): Distinct Clusters Target Individuals of Interest to Russia

Suspected Russian clusters abuse OAuth and authentication flows to phish academia, defense, government, and think tank targets across Europe and the US.

Google Threat Intelligence Group (GTIG) is tracking three distinct suspected Russian cyber espionage clusters abusing legitimate authentication flows. Newly detailed clusters UNC7005 and UNC5976 conduct phishing, abuse OAuth flows, and/or deploy malware, alongside previously reported UNC6293 phishing operations. Targets include individuals in academia, aerospace and defense, governments, and think tanks across Europe, as well as academia and think tanks in the United States.

Google Threat Intelligence · 27d agoThreat actor in the wild