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Critical NetScaler Vulnerability Exploited in Attacks

CISA added critical Citrix NetScaler flaw CVE-2026-19490 (CVSS 9.3) to its KEV catalog after confirming exploitation of gateway and AAA virtual servers in the wild.

CISA warned that threat actors are exploiting CVE-2026-19490, a critical-severity flaw (CVSS 9.3) affecting NetScaler ADC and NetScaler Gateway appliances configured as a gateway (SSL VPN, ICA Proxy, CVPN, RDP Proxy) or AAA virtual server. Citrix patched the bug on August 19, and Rapid7 warned it is remotely exploitable without authentication. Sensor data from Previdian shows exploitation ongoing since at least September 3, one day after a public exploit appeared on GitHub, with matching requests observed from three IPs across three countries. CISA added the flaw to its Known Exploited Vulnerabilities catalog, giving federal agencies three days to patch under BOD 26-04.

SecurityWeekupdated · 6d agofirst · 6d agoExploit / PoC in the wild 6 sourcesCVE-2026-194902· 2 reads

Chaotic Eclipse Released GreenSection, A PoC For NVIDIA Memory Corruption Zero-Day

Researcher Chaotic Eclipse released GreenSection, a PoC exploiting an unpatched out-of-bounds write in NVIDIA Windows user-mode shared memory.

Security researcher Chaotic Eclipse disclosed an out-of-bounds write in NVIDIA's Windows user-mode components, which share a global memory section (\BaseNamedObjects\{52813408-3561-4705-820a-2b3b78be92ba}) with full read/write access to all users. The PoC crashes applications running Vulkan or OpenGL; the researcher says the bug could cross user boundaries or compromise dwm.exe but did not fully assess the impact. No CVE has been assigned and no patch is mentioned. The researcher recently released zero-day PoCs against Kaspersky, Avast, and CrowdStrike Falcon.

Security Affairs · 9d agoExploit / PoC 2 sources

Chaotic Eclipse Releases GenDigital Avast Antivirus ZeroDay PrettyPrague

Researcher Chaotic Eclipse released PrettyPrague, a PoC zero-day privilege escalation exploit against fully patched GenDigital Avast Antivirus.

Security researcher Chaotic Eclipse (also known as INFINITE NIGHTMARE or MSNightmare) published a PoC named PrettyPrague exploiting a zero-day privilege escalation flaw in Avast Antivirus. The PoC abuses a flaw in the Avast Sandbox to dump the Windows SAM database and spawn a SYSTEM-level shell, reportedly working on fully patched Avast and patched Windows 11 25H2. The researcher believes the flaw may also affect other GenDigital products such as AVG and Norton. It follows his recent HardBreacher PoC for a Kaspersky Endpoint Security privilege escalation flaw.

Security Affairs · 15d agoExploit / PoC

Chaotic Eclipse Releases Kaspersky Zero

Researcher Chaotic Eclipse released HardBreacher, a PoC privilege-escalation exploit for Kaspersky Endpoint Security on fully patched Windows 11 25H2.

Security researcher Chaotic Eclipse, also known as INFINITE NIGHTMARE and Nightmare-Eclipse, released a PoC zero-day exploit named HardBreacher targeting Kaspersky Endpoint Security v14.0.0.504. The exploit achieves privilege escalation on fully patched Windows 11 25H2, creating a DLL in System32 with full user permissions and potentially disrupting Kaspersky's UI process and file-access controls. The PoC is unstable and may require repeated attempts; Kaspersky claims it has already addressed the vulnerability.

Security Affairs · 15d agoExploit / PoC1

CISA Adds Seven Exploited Flaws as Attackers Deploy Reverse Shells and Crypto Miners

CISA added seven actively exploited vulnerabilities to its KEV catalog, including SonicWall SMA 1000 SSRF CVE-2026-83548, amid campaigns deploying reverse shells and crypto miners.

CISA's KEV additions cover flaws in SonicWall SMA 1000 (CVE-2026-83548, CVE-2026-83549), Sangoma Switchvox (CVE-2026-9586), JFrog Artifactory (CVE-2026-82329), Kludex Starlette (CVE-2026-48710), Kestra OSS (CVE-2026-49869) and Berri LiteLLM's MCP endpoint (CVE-2026-59822). SonicWall confirmed active exploitation of the SMA 1000 flaws, while Microsoft and Wiz reported attackers chaining LiteLLM flaws CVE-2026-42271 and CVE-2026-48710 to fingerprint hosts, steal provider API keys and deploy XMRig miners on AI infrastructure. Wiz linked exploitation of the LiteLLM chain to the Qilin ransomware group, and Microsoft detailed a Kestra compromise chain ending in cryptocurrency mining and data harvesting via exposed RAGFlow flaws.

The Hacker News · 13d agoExploit / PoC in the wildCVE-2026-83548CVE-2026-83549CVE-2026-9586+10 CVEs1

Nightmare-Eclipse Strikes Again with 'ShieldCrash' Windows Exploit

A researcher known as Nightmare-Eclipse published another zero-day exploit, dubbed ShieldCrash, targeting Windows Defender.

Dark Reading reports that the disgruntled researcher tracked as Nightmare-Eclipse continued a vendetta against Microsoft by publishing a new zero-day exploit named ShieldCrash for Windows Defender. The brief report does not detail affected versions, exploitation prerequisites, or whether exploitation has been observed.

Dark Reading · 6d agoExploit / PoC1

Attackers exploit critical SharePoint flaw after PoC goes public (CVE-2026-55040)

Attackers use Rapid7's public PoC to exploit CVE-2026-55040, a critical SharePoint authentication bypass patched in July 2026.

Rapid7 researcher Stephen Fewer published technical analysis and PoC exploit code for CVE-2026-55040, an authentication bypass in SharePoint caused by flaws in the JWT token validation pipeline. Threat intelligence firm Defused observed attackers using the PoC against SharePoint honeypots, though Microsoft has not yet confirmed in-the-wild exploitation. Chained with CVE-2026-63520, the flaw can yield unauthenticated remote code execution, per NHS England Digital. CISA is urging administrators to harden SharePoint deployments by limiting direct internet exposure and using Layer 7 reverse proxies.

Help Net Security · Aug 13, 2026Exploit / PoC in the wildCVE-2026-55040CVE-2026-63520