Latest cybersecurity reporting from selected sources.

CISA confirms BlueHammer (CVE-2026-33825) is now used in ransomware attacks to gain SYSTEM privileges through Microsoft Defender. BlueHammer, tracked as CVE-2026-33825, has moved from proof-of-concept noise to real ransomware attacks in the wild, the US CISA confirms. BlueHammer allows attackers to escalate privileges locally in Microsoft Defender. The vulnerability, along with two other zero-days dubbed […]

Cisco has released security updates to patch a critical-severity Unified Communications Manager (Unified CM) flaw that allows attackers to gain root privileges. [...]

Cisco has patched an ISE vulnerability with public proof-of-concept exploit code that can be abused by attackers with admin privileges. [...]

Validated, Weaponized Exploit Code for Widely Used Web Framework Bug Now PublicWarnings continue to mount over a critical vulnerability in the widely used web application framework React, with threat intelligence analysts warning that it's being actively targeted by Chinese nation-state groups, and that a legitimate, weaponized proof-of-concept exploit is now public.

Researchers have released proof-of-concept (PoC) exploits for a critical Citrix NetScaler vulnerability, tracked as CVE-2025-5777 and dubbed CitrixBleed2, warning that the flaw is easily exploitable and can successfully steal user session tokens. [...]

CISA has warned U.S. federal agencies about attackers targeting a high-severity vulnerability in the Linux kernel's OverlayFS subsystem that allows them to gain root privileges. [...]

Also: Lee Enterprises Recovering From Ransomware Attack, an Ivanti POCThis week, a FBI warning on Ghost ransomware, Lee Enterprises confirmed its ransomware attack, a proof-of-concept for Ivanti EPM flaws and a cybersecurity flaw in a Xerox machine. Also, a Chinese cyberespionage hacker apparently moonlighted as a ransomware attacker and NioCorp hit by a cyber heist.

Cisco has released security updates to patch a ClamAV denial-of-service (DoS) vulnerability, which has proof-of-concept (PoC) exploit code. [...]

Adobe has released out-of-band security updates to address a critical ColdFusion vulnerability with proof-of-concept exploit code. [...]

SaaS seller sets severity to 'critical' Adobe's patch for a remote code execution (RCE) bug in Acrobat doesn't mention that the vulnerability is considered a zero-day nor that a proof-of-concept (PoC) exploit exists, a researcher warns.…

When PoC code is released within a day of disclosure, it's only a matter of time before attacks kick off The UK's NHS is warning of the possibility that vulnerabilities in Arcserve Unified Data Protection (UDP) software are being actively exploited.…

Google is warning of multiple threat actors sharing a public proof-of-concept (PoC) exploit that leverages its Calendar service to host command-and-control (C2) infrastructure

VMware warned customers on Monday that proof-of-concept (PoC) exploit code is now available for an authentication bypass flaw in vRealize Log Insight (now known as VMware Aria Operations for Logs). [...]

Lexmark has released a security firmware update to fix a severe vulnerability that could enable remote code execution (RCE) on more than 100 printer models. [...]

Cisco has warned of two security vulnerabilities affecting end-of-life (EoL) Small Business RV016, RV042, RV042G, and RV082 routers that it said will not be fixed, even as it acknowledged the public availability of proof-of-concept (PoC) exploit

Proof-of-concept exploit code is now publicly available online for a critical authentication bypass security flaw in multiple VMware products that enables attackers to gain admin privileges. [...]

Publicly released proof-of-concept exploits are supercharging attacks against unpatched systems, CISA warns.

Cisco has patched multiple critical security vulnerabilities impacting its RV Series routers that could be weaponized to elevate privileges and execute arbitrary code on affected systems, while also warning of the existence of proof-of-concept (PoC) exploit code targeting some of these bugs