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You’re Back In The Room (Citrix NetScaler Pre-Auth RCE CVE-2026-8452(?))

watchTowr Labs details a pre-authentication remote code execution flaw, tracked as CVE-2026-8452, in Citrix NetScaler appliances.

watchTowr Labs published technical analysis of a pre-authentication remote code execution vulnerability in Citrix NetScaler, tentatively assigned CVE-2026-8452. The CVE identifier is marked as provisional in the write-up. No confirmation of in-the-wild exploitation is provided in the available text.

watchTowr Labs · Aug 14, 2026Exploit / PoCCVE-2026-8452

New Mirai Variant Targeting Network Security Devices

New Mirai botnet variant exploits nine vulnerabilities in SonicWall, D-Link, Netgear, and other devices, with attacks ongoing at publication.

Unit 42 observed attacks exploiting VisualDoor (SonicWall SSL-VPN), CVE-2020-25506 (D-Link DNS-320), CVE-2020-26919 (Netgear ProSAFE Plus), and other flaws, with infrastructure rotating across at least three IP addresses between February 16 and March 13, 2021. Payloads were updated hours after CVE-2021-27561 and CVE-2021-27562 (Yealink Device Management, unauthenticated root RCE) and later added CVE-2021-22502 (Micro Focus Operation Bridge Reporter) and CVE-2019-19356 (Netis WF2419). Successful exploitation invokes wget to fetch shell scripts that download Mirai binaries compiled for multiple architectures and brute-forcers, and attacks were still ongoing when reported.

Palo Alto Unit 42 · 28d agoExploit / PoC in the wildCVE-2020-25506CVE-2020-26919CVE-2019-19356+3 CVEs

Human Attacker Exploits Marimo RCE, Reaches SSH Bastion in Eight Seconds

Sysdig documents a skilled human attacker exploiting Marimo pre-auth RCE CVE-2026-39987 (CVSS 9.3), reaching an SSH bastion in eight seconds without AI tooling.

Sysdig detailed exploitation of CVE-2026-39987 (CVSS 9.3), a pre-authenticated RCE affecting all Marimo versions that came under active exploitation within hours of disclosure. A human operator used a hand-written Python script to harvest an AWS key from Secrets Manager and SSH into a bastion host in eight seconds, issuing 850+ commands over nine hours. Separately, Hunt.io disclosed an XMRig cryptomining campaign compromising 3,562 Redis servers via SLAVEOF rogue replication and AOF authorized_keys injection. Operation CameraSwarm, linked to a single operator, compromised over 14,000 Dahua IP cameras using CVE-2021-33044 and CVE-2021-33045.

CVE-2026-82435: Apache Storm Worker: Unauthenticated Remote Memory Exhaustion in the Worker Messaging Decoder

Unauthenticated remote memory exhaustion in Apache Storm Worker 3.0.x Netty decoder fixed in 3.1.0, allowing pre-auth denial of service.

CVE-2026-82435 (rated important) affects Apache Storm Worker (org.apache.storm:storm-client) versions 3.0.0 before 3.1.0. The worker's Netty message decoder sits ahead of SASL authentication handlers and processes frames before any authentication occurs. It allocates buffers sized from an attacker-controlled length field, so a single frame from an unauthenticated peer reaching the worker can exhaust memory. Users must upgrade to 3.1.0.

oss-security · 2d agoVulnerabilityCVE-2026-824353

Off Guard: Breaking LiteLLM from authentication bypass to cloud compromise

Wiz found LiteLLM auth bypass (CVE-2026-59822) and post-auth RCE (CVE-2026-59821) chainable to cloud compromise; the bypass is in CISA KEV with in-the-wild exploitation.

Wiz scanned roughly 3,074 internet-facing LiteLLM deployments and found 9.6% accepted the default master key sk-1234 or required no authentication, making post-auth attacks effectively pre-auth. The MCP endpoint accepts any Bearer token and grants a valid session (CVE-2026-59822), confirmed exploited in the wild via honeypots and added to CISA's Known Exploited Vulnerabilities catalog. Custom code guardrails allow post-auth root-level RCE via exec(compile(...)) (CVE-2026-59821), while pass-through endpoints lack URL validation, enabling cloud credential theft in post-auth scenarios. All assigned vulnerabilities have been patched; the research was presented at DEF CON 34.

Wiz Blogupdated · 6d agofirst · 6d agoExploit / PoC in the wild 4 sourcesCVE-2026-59822CVE-2026-598211

2026-008: Critical vulnerabilities in Ivanti Sentry

Ivanti patched Sentry: pre-auth OS command injection CVE-2026-10520 (CVSS 10) enables unauthenticated root RCE, and auth bypass CVE-2026-10523 (CVSS 9.9).

On 9 June 2026 Ivanti released an advisory fixing two critical flaws in Ivanti Sentry versions 10.5.1 and prior, 10.6.1 and prior, and 10.7.0 and prior. CVE-2026-10520 (CVSS 10.0) is an OS command injection allowing a remote unauthenticated attacker to achieve root-level RCE. CVE-2026-10523 (CVSS 9.9) is an authentication bypass letting an unauthenticated attacker create arbitrary administrative accounts and obtain full admin access. CERT-EU recommends updating appliances to fixed versions following Ivanti's guidance.

Hackers Are Probing PaperCut Servers, and 47% Still Have No Patch

PaperCut pre-auth RCE CVE-2026-81578 actively exploited; 47% of tracked installs unpatched and exposed to remote code execution.

Huntress confirmed active exploitation of a pre-authentication RCE flaw in PaperCut (CVE-2026-81578), chainable with CVE-2026-82078 to achieve SYSTEM-level code execution via PaperCut's Application Server. Observed attacks focused on short reconnaissance (whoami, ver, tasklist) with no persistence, but a malicious Java class dropping into the installation directory leaves the jdbc:derby:memory:pwn breadcrumb. Roughly 47% of ~2,500 tracked installations run version 23 or earlier with no patch yet available.

Security Affairs · 10d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078

U.S. CISA adds PaperCut NG/MF flaws to its Known Exploited Vulnerabilities catalog

CISA added two actively exploited PaperCut NG/MF pre-auth flaws to the KEV catalog; federal agencies must patch by September 14.

CISA added CVE-2026-81578 (CVSS 8.8, missing authentication for critical function) and CVE-2026-82078 (CVSS 9.4, unsafe reflection) in PaperCut NG/MF to its Known Exploited Vulnerabilities catalog. Huntress confirmed active pre-authentication RCE exploitation in two customer environments and reproduced the full chain against a clean PaperCut NG 25.0.11 server, chaining the auth bypass into unsafe Java class loading for SYSTEM-level execution. About 47% of roughly 2,500 tracked PaperCut installs still run version 23 or earlier with no patch available, and observed attacker activity was limited to system discovery commands.

Security Affairs · 15d agoVulnerability in the wildCVE-2026-81578CVE-2026-82078

PaperCut NG/MF vulnerabilities exploited in zero-day attacks

PaperCut warns of active zero-day exploitation chaining CVE-2026-81578 and CVE-2026-82078 for pre-auth remote code execution in NG/MF print management.

PaperCut Software confirmed attackers are chaining two vulnerabilities in PaperCut NG and MF: CVE-2026-81578, an improper access control flaw in the web management interface allowing unauthenticated configuration changes, and CVE-2026-82078, unsafe dynamic class loading in database connection utilities enabling arbitrary Java bytecode execution. Huntress reproduced a pre-authentication remote configuration takeover and full RCE chain against PaperCut NG 25.0.11.75758 and observed limited exploitation at two customers, including post-exploitation whoami and ver commands. The vendor released Emergency Patch Release 2 with additional hardening and urged restricting Application Server web access to trusted IPs. In 2023, Clop and LockBit affiliates abused CVE-2023-27350 and CVE-2023-27351 in the same software.

Help Net Security · 15d agoExploit / PoC in the wildCVE-2026-81578CVE-2026-82078CVE-2023-27350+1 CVEs1