N-able N-central Pre-Auth RCE Flaw Exploited in the Wild
CISA added CVE-2026-86218 (CVSS 10.0), a pre-auth RCE in N-able N-central, to KEV after N-able confirmed in-the-wild exploitation; patch by September 11.
CISA added CVE-2026-86218, a maximum-severity static code injection flaw enabling pre-authentication remote code execution in N-able N-central, to its Known Exploited Vulnerabilities catalog with a September 11, 2026 deadline for federal agencies. The flaw is fixed in N-central 2026.3 Hotfix 4 (released September 5), and N-able told customers it has been observed being exploited in the wild. Separately, Huntress is investigating the compromise of a fully patched customer N-central environment on September 4 and cannot yet confirm which flaw was used, while Rapid7-disclosed CVE-2026-86206 and CVE-2026-86207 can be chained by an unauthenticated attacker to create a rogue System Administrator account.
CVE-2026-86206, CVE-2026-86207: N-able N-central Authentication Bypass (FIXED)
Rapid7 disclosed two chained N-able N-central flaws, CVE-2026-86206 and CVE-2026-86207, enabling unauthenticated admin account creation; patched in 2026.3 Hotfix 3.
Rapid7 researchers found CVE-2026-86206 (semicolon/Forwarded access-control bypass, CWE-791, CVSSv4 6.9) and CVE-2026-86207 (UserTwoFactorLogin authentication bypass, CWE-305, CVSSv4 7.7) in the latest N-able N-central. Chained, they let a remote unauthenticated attacker create an attacker-controlled System administrator account. The bugs stem from Envoy and Jetty disagreeing on the requested path and whether the client is local. N-able patched both in N-central 2026.3 Hotfix 3, following the earlier CVE-2026-18577 authentication bypass.
N-able patches critical N-central zero-day exploited in the wild (CVE-2026-86218)
N-able shipped an emergency hotfix for CVE-2026-86218, a pre-auth RCE zero-day in N-central RMM observed exploited in the wild.
N-able released Hotfix 4 for N-central 2026.3 on September 5 (build 2026.3.1.14), fixing CVE-2026-86218, a critical pre-authenticated remote code execution flaw in its RMM platform popular with MSPs. A private customer notice marked urgent said the zero-day 'has been observed being exploited in the wild,' while the public advisory said there were no confirmed production exploits. Huntress also flagged two high-severity vulnerabilities, CVE-2026-86206 and CVE-2026-86207, which allow authentication bypass and unrestricted access; they were patched the same weekend and were discovered by Rapid7's Stephen Fewer. N-able advised auditing N-central user accounts for unexpected users.
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.