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Cybersecurity researchers have shed light on a WordPress compromise in which threat actors deployed multiple persistence mechanisms to ensure that the final payload kept returning without having to infect the site again. The backdoor has been codenamed SC after the "SC_" markers present in the injected content. Sucuri has described the malware as a "self-healing mesh" that's blockchain-controlled. "The payload lives in at least eight places at once, spread across files, the database, and shared memory, and every one of those places can rebuild all the others," security researcher Gabriel Barbosa said . "Delete the plugin and a drop-in rewrites it. Delete the drop-in and the theme rewrites it. Clean every file on disk, and the next page load restores the whole set from the database or from a shared-memory segment. The result is a circular system with no single point you can remove to stop it." According to Sucuri, the malware does no...

Every security leader at a bank, insurer, or asset manager has had a version of this conversation: Security wants to eliminate a class of vulnerabilities. Engineering explains what it would take to upgrade the platform where they live. Somebody prices out the regression testing. Somebody else raises the change-freeze calendar. The finding gets an exception, a compensating control, and a date eighteen months out on the roadmap to address it. Nobody in that conversation is being unreasonable. Financial services carry more legacy software than almost any other industry for a few reasons: decades of accumulated infrastructure, regulatory obligations that reward stability, and applications where an hour of downtime is unacceptable. In that environment, minimizing change is risk management. Every dependency bump, every base image swap, every migration is a chance to break something that clears trades or moves money. So the instinct to stick to the status quo has been sound. The problem...

OpenAI on Wednesday said it identified and disrupted a coordinated distillation campaign that was designed to illicitly extract protected reasoning from its artificial intelligence (AI) models. A "core cluster of the activity," going back to the first week of July, has been attributed to individuals associated with Moonshot AI, a Chinese AI company based in Beijing. It did not cite any technical evidence to back this assessment, likely owing to security reasons. "The operators did not break our encryption, compromise a database, or gain direct access to stored user conversations," OpenAI said . "Instead, they manipulated model interactions so that protected reasoning could be reproduced in forms visible to the requester in a coordinated, scaled manner that violated our terms of service." The activity is said to have begun on July 1, 2026, initially at a low volume before it spiked on July 24 and 25, 2026, to 16,000 attempted requests using a relevan...

The U.S. Cybersecurity and Infrastructure Security Agency (CISA) on Wednesday added a critical authentication bypass flaw impacting Cisco Catalyst SD-WAN Manager to its Known Exploited Vulnerabilities ( KEV ), following reports of active exploitation. The vulnerability, tracked as CVE-2026-76504 (CVSS score: 9.8), could allow an unauthenticated, remote attacker to access an affected system with the privileges of the admin user. "Cisco Catalyst SD-WAN Manager contains a hex encoding vulnerability that could allow an unauthenticated, remote attacker to access an affected system with privileges of the admin user due to improper handling of URI encoding in an HTTP request," CISA said. Successful exploitation could allow an attacker to sidestep authentication by sending a crafted HTTP request to the API of the affected system, and gain access to the API as the admin user.

Google on Wednesday announced its latest frontier artificial intelligence (AI) model, Gemini 4 Argon , that it said is being rolled out to a set of trusted cyber defenders through its Fairwind Program. "It delivers frontier performance in complex workflows across real-world software engineering, enterprise knowledge work like legal and finance, and cybersecurity defense," Koray Kavukcuoglu, senior vice president of Google DeepMind and Chief AI Architect at Google, said . The development comes nearly a month after the tech giant unveiled Gemini 3.8 Flash Cyber , which it described as the most capable cybersecurity model. Like similar models from rivals Anthropic and OpenAI, Argon is assessed to be highly capable at autonomously finding, validating, and patching critical software vulnerabilities. This includes a previously unknown critical vulnerability exposing sensitive personal information across healthcare software used by hospitals worldwide. Google did not reveal...

Security researchers have published the first public proof-of-concept for CVE-2026-86950 , an Apple CoreGraphics flaw Apple says may have been used in attacks against specific targeted individuals. The trigger is a malicious PDF with a crafted embedded font that crashes unpatched iPhones and Macs. The code causes a crash, not an execution error. Turning the memory corruption into a working exploit is separate work the analysis does not demonstrate. Apple patched the flaw on  September 28 , crediting Meta Product Security with the discovery and noting it may have been used in an "extremely sophisticated attack against specific targeted individuals on versions of iOS before iOS 27." The U.S. Cybersecurity and Infrastructure Security Agency  added the flaw  to its Known Exploited Vulnerabilities catalog the following day, requiring federal agencies to apply the fix by October 2. Apple has not listed iOS 27 or macOS Golden Gate 27 as affected in the September 28 advi...

Cryptocurrency exchange Bitget on Wednesday confirmed that attackers who stole $387.5 million last week exploited a zero-day flaw in third-party security products, citing ongoing investigation findings from SlowMist. "Their investigation identified malicious activity involving third-party security products, including a zero-day vulnerability, and recovered a customized tool used by the attacker to initiate unauthorized withdrawals," Bitget said in a post on X. On September 24, 2026, the cryptocurrency exchange disclosed that threat actors stole $387.5 million from its hot and warm wallets through a series of unauthorized transfers, prompting it to halt all withdrawals temporarily. Close to $1.1 million in cryptocurrency assets have been frozen by Circle, Tether, and NEAR Intents. In a subsequent analysis , Bitget said the attackers exploited the flaw to obtain high-level internal credentials and use them to issue fraudulent withdrawal commands to the wallet system ...

Threat actors have been observed exploiting a critical pre-authentication command injection vulnerability in Citrix NetScaler ADC and NetScaler Gateway to drop web shells and attempt theft of configuration data. LevelBlue's Threat Hunt Operations & Research (THOR) team, which analyzed the exploitation activity across multiple customer environments, said it identified malicious NetScaler authentication events containing attacker-controlled usernames designed to weaponize CVE-2026-88771. CVE-2026-88771 (CVSS score: 9.5) is an improper input validation vulnerability that could allow an unauthenticated attacker to execute arbitrary commands.  The security flaw, along with CVE-2026-88772, was disclosed last week after reports that the Dutch National Cyber Security Centre (NCSC-NL) reportedly sent a pre-notification to organizations in the Netherlands that urged organizations to shut their appliances down, citing active exploitation. As of writing, there are currently no d...

Threat actors have weaponized a now-patched security flaw in Zimbra Collaboration Suite (ZCS) to deploy web shells and access mailbox data, according to findings from the Microsoft Security Research team. The attack exploits CVE-2026-73570 (CVSS score: 8.9), an unauthenticated operating system command injection flaw that can lead to remote code execution when Simple Network Management Protocol (SNMP) notifications are enabled and the optional zimbra-snmp package is installed. Exploitation of CVE-2026-73570 can be triggered by a specially crafted SMTP request (i.e., email) against exposed Zimbra servers without requiring authentication or user interaction. The vulnerability was patched by Zimbra in July 2026 with the release of version 10.1.20. "Following successful exploitation, observed activity included deployment of JSP web shells and reverse shells, privilege escalation, persistent remote-access tooling, and memory-backed execution," the tech giant said . "Th...

Attackers are exploiting a new critical zero-day flaw in Cisco Catalyst SD-WAN Manager, the system companies use to manage their Cisco SD-WAN networks, Cisco said in an  advisory  on September 30. The flaw, CVE-2026-76504 , could allow a remote attacker with no login access to use the Manager's API as the admin user. Fixed releases are available, and there is no workaround. It carries a CVSS score of 9.8 out of 10. It sits in the part of the Manager's API that handles login sessions. The Manager mishandles URI encoding in an HTTP request. A crafted request can therefore bypass an authentication rule intended to restrict access to a single API endpoint. The attacker needs no credentials, only the ability to send that request to the Manager's API. Managers exposed to the internet are at risk of compromise, according to Cisco. By default, the admin user holds the netadmin role, which is allowed to perform all operations on the device. Cisco said its Product Security I...

Unknown threat actors have been observed exploiting a newly patched security flaw in Citrix NetScaler ADC and NetScaler Gateway appliances to target organizations in North America and Europe. The activity, observed by Mandiant Consulting and Google Threat Intelligence Group (GTIG) in September 2026, has targeted government, financial services, technology, education, and legal and professional services sectors. In a post shared on LinkedIn, Charles Carmakal, chief technology officer at Mandiant Consulting, said the targeted intrusions have impacted dozens of organizations, warning of "broad and opportunistic exploitation of CVE-2026-88772 and CVE-2026-88771 by a variety of threat actors in the near term." "Exploitation of CVE-2026-88772 bypasses authentication and triggers an unhandled termination of the NetScaler Packet Processing Engine (NSPPE) to establish initial root-level access," the tech giant said . The attacks have been observed weaponizing the f...

A High-severity OpenSSL flaw can leak heap memory to the other side of a DTLS connection or crash the program,  OpenSSL said  on September 29 as it released fixes. DTLS , the TLS variant used for UDP traffic, resends a handshake message if no reply arrives before the timer expires. The leak or crash can happen when such a resend starts while a larger handshake message is stuck part-way through being sent. The flaw, tracked as CVE-2026-84782, is fixed in  OpenSSL 4.0.3, 3.6.5, 3.5.9 and 3.4.8 . Fixed versions for the older 3.0, 1.1.1 and 1.0.2 branches go only to customers who pay for OpenSSL's premium support. OpenSSL 3.0  stopped getting public security fixes  on September 7. OpenSSL has not said whether an attacker can cause a resend while a message is stuck, nor has it reported any attacks exploiting the flaw. DTLS is used, for example, to protect WebRTC data channels and to set up encryption keys for internet calls. Software is exposed to this fla...

Cybersecurity researchers have disclosed technical details of a recently patched critical security flaw in Citrix NetScaler ADC and Gateway that has come under active exploitation in the wild. The vulnerability, tracked as CVE-2026-88772 (CVSS score: 9.5), has been described as a memory overflow bug in the Datagram Transport Layer Security (DTLS) protocol handling that's rooted in the NetScaler Packet Processing Engine (NSPPE). "Citrix NetScaler ADC and NetScaler Gateway contain an improper restriction of operations within the bounds of a memory buffer vulnerability that could allow for remote code execution or denial-of-service," the U.S. Cybersecurity and Infrastructure Security Agency (CISA) said . The issue, per watchTowr , is that NetScaler implicitly trusts the declared fragment size in the DTLS handshake header's fragment_length field (i.e., 1 byte), while the header simultaneously claims that the complete message, as denoted by the length field, is 120...

A group of academics from VUSec and Scuola Superiore Sant'Anna have disclosed details of a new Spectre CPU vulnerability variant that affects Just-In-Time ( JIT ) engines present in web browsers, language runtimes, and the operating system kernel, across multiple CPU vendors. The new Spectre v2 variant has been codenamed Branch Target Reuse (BTR) . "The key insight is that, while modern CPUs restore architectural code coherence after self-modification, they do not necessarily invalidate stale indirect branch prediction entries (i.e., branch targets)," researchers Sander Wiebing, Yuhui Zhu, Alessandro Biondi, and Cristiano Giuffrida said in an accompanying paper. "In JIT engines, these stale targets can outlive the original code and later be reused when the code cache is repopulated, yielding a transient execute-after-free primitive. This allows attackers to hijack transient control flow to newly generated code at obsolete offsets, bypassing software hardening...

Kiteworks on Monday said it worked with federal intelligence authorities over the weekend as it identified and addressed a critical security vulnerability during the scheduled precautionary shutdown . "During the shutdown, this activity led to the discovery of a previously unknown critical vulnerability confined to a capability that is enabled for less than 1% of the customer base," the company said in a statement. "Kiteworks developed and deployed a fix during the window, [and] applied an additional protective layer across all environments." There is no evidence that the vulnerability has ever been exploited in a malicious context. Other Kiteworks products are not affected by the flaw. The development comes days after Kiteworks, previously Accellion, urged customers to take their systems offline for a period of nine hours, in addition to shutting down environments it hosts on behalf of customers, after receiving intelligence about a potential imminent cybe...

Dutch authorities have confirmed that they arrested a 24-year-old man from Amsterdam in connection with the ShinyHunters group. "It is true that this month a 24-year-old man from Amsterdam was arrested in an investigation into the hacker group ShinyHunters," the Politie Landelijke Opsporing en Interventies said in an X post Monday. Police said the individual is expected to appear before the Rotterdam District Court on September 29, 2026. Although law enforcement officials did not disclose any additional details, independent security journalist Brian Krebs and DataBreaches.Net identified the arrested man as Pepijn van der Stap (aka Umbreon), who was previously apprehended in 2023 for his role in a series of data thefts and extortions. Per DataBreaches.Net, van der Stap was arrested on September 15, 2026. In 2023, it emerged that the individual worked at cybersecurity company Hadrian and volunteered at the Dutch Institute for Vulnerability Disclosure (DIVD). ...

A malicious MCP server could trick an application built on the official  MCP Python SDK  into handing over the OAuth credentials it uses to log in to a real service, the SDK's maintainers said in a security advisory. Affected versions sent the client secret, the authorization code, and the PKCE proof key to a token endpoint the attacker controlled. The fix is in versions 1.30.0 and 2.2.0. The Model Context Protocol (MCP) is an open standard for connecting AI applications to outside tools and data, and this package is its official Python SDK for building MCP servers and clients. With the stolen credentials, the attacker can request a valid access token from the real login service. Cycode, the security firm that reported the flaw , demonstrated that full exchange in a test and says the resulting token carries whatever permissions the app was granted. The client secret is long-lived, so it keeps working until it is changed. The flaw is rated high (7.5) for the two prov...

Apple has released security updates to address a vulnerability in older versions of iOS, iPadOS, and macOS that it said may have been exploited in targeted attacks. The vulnerability, tracked as CVE-2026-86950 , refers to an out-of-bounds write impacting the CoreGraphics component that could lead to arbitrary code execution when processing a maliciously crafted file. The iPhone maker said the issue was addressed with improved bounds checking. It credited Meta Product Security with discovering and reporting the issue. "Apple is aware of a report that this issue may have been exploited in an extremely sophisticated attack against specific targeted individuals on versions of iOS before iOS 27," it added. However, the company offered no details on how many individuals were targeted, if any of those attempts were successful, or when the first instance of CVE-2026-86950 exploitation occurred. The shortcoming has been addressed in the following devices and operating syste...

The attacker who stole about $388 million from the cryptocurrency exchange Bitget gained access through a vulnerability in a third-party security product the exchange used, Bitget said on Monday. The attacker exploited the flaw to obtain high-level internal credentials and then, on September 24, used them to send fraudulent withdrawal commands to Bitget's wallet system. Exchanges keep most customer funds in offline cold wallets and use hot and warm wallets to process withdrawals. Transfers from those wallets must still be approved before they are signed. The stolen funds came from part of Bitget's hot and warm wallets, and its cold wallets were not affected. Bitget  said last week  that a critical backend system in its wallet infrastructure had been compromised and used to spoof transaction data and trigger its approval process. It had not said how the attacker got in. Bitget CEO Gracy Chen described the attack on Monday in a livestream, in an interview with  The...

A domain used as harmless placeholder text showed up in roughly 1,700 repositories. Then somebody registered it and started serving malicious lures. That is the kind of week this was: forgotten assumptions turning into live attack surface. Elsewhere, weak service accounts, old bugs, exposed systems, phishing kits, and strangely easy exploit paths kept doing useful work for attackers. Nothing exotic. Mostly things nobody expected to matter anymore. Here’s the full recap of what mattered this week. ⚡ Threat of the Week Citrix Warns of Actively Exploited NetScaler ADC and Gateway Flaws — Citrix released patches to address multiple vulnerabilities, including CVE-2026-88771 and CVE-2026-88772, that have come under active exploitation. CVE-2026-88771 is an improper input validation vulnerability that could allow an unauthenticated attacker to execute arbitrary commands, while successful exploitation of CVE-2026-88772 could allow for remote code execution or denial-of-service. CISA...