Threat Intelligence / CVE / CVE-2026-91843

CVE-2026-91843 — checkpoint Quantum Security Management

CVSS v3.1 9.8 (CRITICAL) · Priority 6.9/10 · Published 2026-09-16

As of 2026-09-17, CVE-2026-91843 is a CRITICAL-severity vulnerability in checkpoint Quantum Security Management, CVSS v3.1 9.8. Threadlinqs Intelligence links 2 tracked threat campaigns to CVE-2026-91843, most recently “Eclypsium InfraTrust Report: Mass Active Exploitation of Network Management Systems (Cisco FMC/ISE CVE-2026-20079, CVE-2026-76460; SonicWall SMA 1000 CVE-2026-83548/83549; Linux Kernel CopyFail CVE-2026-31431)”.

Last updated: 2026-09-17

What is CVE-2026-91843?

A stack overflow during the unauthenticated login process may allow an attacker to run arbitrary code remotely with root privileges.

The record classifies CVE-2026-91843 under weakness class CWE-121. Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on confidentiality, integrity, availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 8 days ago.

Severity and exploitation probability

CVSS v3.1 base score
9.8 — CRITICAL
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CISA KEV
Not listed in the CISA Known Exploited Vulnerabilities catalog
Threadlinqs priority
6.9/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
Published
2026-09-16, last modified 2026-09-17

Is CVE-2026-91843 being exploited?

Weaponised exploit code for CVE-2026-91843 is publicly available. 1 public proof-of-concept repository is tracked for this identifier.

Affected products and versions

How to fix CVE-2026-91843

No vendor patch reference has been recorded for CVE-2026-91843 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

Threat activity tracking CVE-2026-91843

2 tracked threats in the Threadlinqs corpus reference CVE-2026-91843, either in the campaign’s CVE list or as an indicator on the campaign record.

Sources

Enriched from CVE.org, NVD, GitHub Security Advisories, public proof-of-concept repositories. Last verified by Threadlinqs on . This product uses the NVD API but is not endorsed or certified by the NVD.

Other references

Full detection coverage & IOCs for threats exploiting CVE-2026-91843 are available via the Threadlinqs MCP server (Purple tier). View plans →

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