CVERadar
MEDIUM · CVSS 3.1 4.3CISA KEV · added 2026-10-30EPSS n/aThreat level 37

CVE-2026-118527: Ivanti Connect Secure Generation of Predictable Numbers or Identifiers Vulnerability

Ivanti · Connect Secure · NVD published 2026-11-03 · posted 2026-11-04 · last modified 2026-11-03

CVE-2026-118527 at a glance

CVE-2026-118527 is a medium-severity vulnerability in Ivanti Connect Secure, with a CVSS 3.1 base score of 4.3. NVD published it on 2026-11-03 and classifies the weakness as CWE-340. CISA added it to the Known Exploited Vulnerabilities catalog on 2026-10-30; the federal remediation due date is 2026-11-13. NVD configuration data lists a fixed release for 1 product, for example ivanti connect secure 25.1.1.3. Its CVERadar threat level is 37/100.

What it is

Use of predictable filenames in Ivanti Connect Secure before versions 25.1.1.3 and 22.8R2.6 allows a remote authenticated attacker to upload files with attacker-controlled content to a known location on disk.

WeaknessCWE-340 definition
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N (source: CVE Numbering Authority)
CISA due date2026-11-13 (for US federal agencies under BOD; a good deadline for everyone)
ATT&CK tacticsn/a

CVERadar report: CVE-2026-118527: Ivanti Connect Secure flaw exploited in the wild, what we know

What this means for a small business

CISA added CVE-2026-118527 to its Known Exploited Vulnerabilities catalog on 2026-10-30. A KEV listing means CISA has evidence that attackers are using the flaw against real systems, not just that it could be used.

If your business runs Ivanti Connect Secure, put this at the top of the patch list. CISA gave US federal agencies until 2026-11-13 to deal with it, and that is a sensible deadline for a small business too.

  • Patch. Update to a fixed release: ivanti connect secure 25.1.1.3 or later. These versions come from NVD's configuration data, so confirm them against the advisory from Ivanti.
  • If you cannot patch yet. Follow CISA's required action: Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.
  • Check your exposure. Find out whether Ivanti Connect Secure can be reached from the internet, for example a VPN portal, an admin login page or a file-transfer site. Your firewall's port-forwarding rules and your IT provider's list of public-facing systems are the quickest places to look. Exposed copies come first.
  • When to call IT support. Call your IT support provider now if you run Ivanti Connect Secure and cannot confirm it is updated, if it was reachable from the internet before you patched it, or if you notice accounts, sign-ins or files you do not recognise. The last two can mean the system was already hit, and checking that properly takes someone who can read the logs.

If nobody on staff owns the firewall, LayerLogix firewall management covers configuration, monitoring and policy reviews.

Built from the CISA KEV entry and the NVD record for CVE-2026-118527; nothing here goes beyond those sources.

Exploitation evidence

First exploit evidence seen: 2026-10-30 (earliest date across the sources below).

Exploited in the wild

Sources: CISA KEV.

No ATT&CK techniques could be mapped or inferred for this CVE yet.

Patches, mitigations and detection

CISA required action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines. (source: CISA KEV)

Fixed versions

  • ivanti connect secure: upgrade to 25.1.1.3 or later (affected from 25.1.0.0)

Derived from the NVD CPE configuration (versionEndExcluding / versionEndIncluding). Always confirm with the vendor advisory.

Vendor advisories and patches

Detection Generic guidance

    Response checklist Generic guidance

    1. Inventory: find every instance of the affected product and version (include internet-facing and forgotten ones).
    2. Patch or mitigate per the vendor advisory; if you cannot patch, remove internet exposure or apply the vendor workaround.
    3. Assume compromise if the system was exposed before patching: hunt for the indicators in the advisory and review logs back to the disclosure date.
    4. Rotate credentials and secrets stored on or used by the affected system if compromise cannot be ruled out.

    Sources