CriticalCVE-2026-104935

    Ivanti Connect Secure Authentication Bypass by Spoofing Vulnerability (CVE-2026-104935)

    Published Last modified In CISA KEV since Sources: BSI, CVE.org, Ivanti

    What is affected, what to do

    Authentication bypass by spoofing in ICS before version 25.1.3.0 allows a remote unauthenticated attacker to execute arbitrary commands. This does not impact ICS version 22.7R2.14 or prior.

    The vulnerability is being actively exploited; treat it as a priority. Update Ivanti Connect Secure to version 22.7R2.14. Immediate actions, mitigation and detection rules are in the runbook below.

    Affected
    • Ivanti Connect Secure lt *..22.7R2.14
    Fixed in
    • Ivanti Connect Secure 22.7R2.14

    Not sure whether and how you are affected? Ask a question about this vulnerability

    Metrics

    8.6

    Priority

    XIEM Effective CVSS: highest available CVSS rating from NVD and vendor data.

    Source: Vendor (CNA), CVSS v3

    8.6

    CVSS v3

    Severity High on the scale from 0 to 10.

    Source: BSI, CVE.org, Ivanti

    26.0 %

    EPSS score

    Elevated — model estimates 10-50% exploitation likelihood.

    Source: FIRST EPSS, percentile 98.0

    Show all metrics
    Severity
    Critical
    Priority score

    The priority score is a consolidated metric that condenses several individual signals into a single, action-guiding ranking: technical severity (CVSS), exploitation likelihood (EPSS), known-exploited status (KEV) and the context of the affected asset. The aim is to answer the only truly important question in vulnerability management: what first?

    Read in glossary
    249.78
    Exploit maturity

    An exploit is code or a technique that specifically uses a concrete vulnerability to force unintended behaviour — such as executing code or escalating privileges. It is the tool that turns a theoretical flaw into a practical attack.

    Read in glossary
    actively exploited (KEV)Source: VulnCheck KEV (opens in a new tab)
    XIEM Effective CVSS

    XIEM® is the tiered managed-security operating model from NEOSEC and a registered trademark of NEOSEC GmbH. It extends classic SIEM — the central collection, normalisation and correlation of security-relevant events — with endpoint forensics, network visibility and deception technology, and consolidates them into three building tiers: Sentry, Orchestrate and Command.

    Read in glossary
    8.6
    CVSS v3

    CVSS is the globally established, open standard for assessing the technical severity of a vulnerability on a scale from 0 to 10. It describes how easily a flaw can be exploited and what damage it can cause — but not how likely its actual exploitation is. CVSS and the complementary EPSS deliberately answer different questions.

    Read in glossary
    8.6
    EPSS score

    The EPSS score is the absolute model output for an individual vulnerability: the estimated probability of real-world exploitation within the next 30 days, expressed as a value between 0 and 1 (i.e. 0 % to 100 %). A score of 0.42 means „the model estimates a 42 % chance of real-world exploitation within 30 days“.

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    26.0 %
    Elevated — model estimates 10-50% exploitation likelihood.
    EPSS percentile

    The EPSS percentile is the relative position of a vulnerability within all EPSS-scored CVEs, expressed as a value between 0 and 1. A percentile of 0.90 means „this CVE has a higher EPSS score than 90 % of all other scored CVEs“. Unlike the EPSS score, it is not a probability — but a positioning within a ranking.

    Read in glossary
    98.0
    Critical — this CVE ranks in the top fifth of all CVEs scored today (rank ≥ 80%).
    KEV status

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    Actively exploited
    Published
    In CISA KEV since

    The KEV catalogue is a list maintained by the US authority CISA of vulnerabilities for which active exploitation in the wild has been confirmed. It answers not the question „how severe?“ but „is it already being attacked?“ — thereby sharply prioritising patching.

    Read in glossary
    CWE

    CWE is a catalogue of typical weakness types in software and hardware — such as flawed input validation, unsafe memory handling or poor authentication. Where a CVE names a concrete vulnerability in a concrete product, a CWE describes the underlying class of defect.

    Read in glossary
    CWE-290

    Response and mitigation

    Why act now?

    Prioritisation rationale

    This flaw is network-reachable without authentication or user interaction and yields command execution on a perimeter device that is internet-facing by design and holds trust relationships into Active Directory. Ivanti VPN gateways have been a favoured target for initial access, persistence and credential harvesting for years, and this CVE's exploitation likelihood ranks among the highest of all scored vulnerabilities. CISA does not currently flag known ransomware use. Treat every internet-exposed ICS instance on the 25.x or 22.8 branch as a critical emergency with a sub-24 h patch SLA plus a compromise assessment. Only instances on 22.7R2.14 or earlier, or non-exposed lab systems, justify lower priority.

    1. Runbook step 1

      Immediate response (0-24 h)

      • Inventory: Enumerate every Ivanti Connect Secure appliance (physical, virtual, cloud) with its exact version. Per NVD, versions before 25.1.3.0 are affected, and 22.7R2.14 and earlier are not affected. The context lists 22.8R2.5 for the 22.8 branch. Confirm the exact per-branch mapping in the Ivanti security advisory.
      • Patch: Upgrade to a fixed build: 25.1.3.0 or 25.1.3.1 on the 25.x branch, or 22.8R2.5 on the 22.8 branch (per vendor data). Run the external Integrity Checker Tool (ICT) before upgrading and preserve the output. Upgrading does not clean an already compromised appliance.
      • Compromise assessment: If ICT reports mismatches, unknown files or anomalous processes, isolate the appliance. Capture forensic images and logs, then factory-reset and rebuild per Ivanti guidance. Do not restore configuration from backups taken after the suspected compromise date.
      • Rotate credentials (on suspicion or if you cannot rule it out): Replace local admin accounts, LDAP/AD/RADIUS bind accounts, API keys, device certificates and private keys, and any secrets stored on the appliance. Kill all active VPN sessions.
      • Cut exposure: Restrict the admin UI to the internal management interface immediately. If you cannot patch within hours, restrict TCP/443 at the perimeter to known source ranges or take the service offline temporarily.
      • Regulatory clock: If exploitation is confirmed, prepare the NIS2 early warning to your national CSIRT/BSI (24 h) and keep a timestamped incident record.

    2. Runbook step 2

      Mitigation layers

      • Network segmentation: Place the ICS appliance in a dedicated DMZ. Allow appliance-originated egress only to defined destinations (AD/LDAP, RADIUS, NTP, DNS, Ivanti update servers), and deny and log everything else. Outbound callbacks are the classic post-RCE payload-staging and C2 signal.
      • Limit lateral movement: From the appliance itself (not the VPN client pool), permit only the internal ports it strictly needs. In particular, block SMB (445), RDP (3389), WinRM (5985/5986) and LDAP write access to domain controllers.
      • WAF/IPS: Front the appliance with a WAF or IPS running current vendor signatures for Ivanti Connect Secure (check your Suricata/Snort rulesets for Ivanti entries). Block requests with anomalous header combinations, oversized header values, or shell metacharacters in path and parameters. The context does not specify which field is spoofed, so tighten the rules against the vendor advisory.
      • IAM/least privilege: Scope the appliance's AD bind account to read-only and bring it under Tier-0 monitoring. Enforce MFA on all VPN realms. MFA won't stop the exploit, but it limits reuse of harvested credentials.
      • Configuration: Disable unused realms, sign-in URLs and features (e.g. unused API endpoints or web interfaces). Forward full syslog to the SIEM and size local log retention so attackers cannot trivially overwrite their traces.

    3. Runbook step 3

      Detection rules

      • Appliance logs (syslog → SIEM): Alert on successful admin or user sessions with no preceding authentication event, admin logins from external IPs, and configuration changes outside maintenance windows. SPL idea: index=ivanti sourcetype=pulse:connectsecure ("Admin" AND "login") | where NOT cidrmatch("10.0.0.0/8", src_ip).
      • Web/reverse-proxy logs: Flag unauthenticated requests to /api/, /dana-ws/ and /dana-na/ that return HTTP 200 on paths that normally require a session, plus URL-encoded shell characters (%3B, %7C, %60, $(). Sigma shape: logsource: webserver; selection: cs-uri-query|contains: ['%3B','%7C','$(']; cs-uri-stem|startswith: '/api/'.
      • Network telemetry (Zeek/Suricata/firewall): Hunt for new egress from the appliance IP to unfamiliar destinations (especially HTTP/HTTPS to VPS providers or DNS lookups for rare domains), and for appliance connections to internal hosts on 445/3389/5985. KQL idea: CommonSecurityLog | where SourceIP == "<ICS-IP>" and DestinationIP !in (allowlist).
      • Integrity checks: Run the external ICT at least daily until the patch is installed and verified. Treat new or modified files as a critical alert, especially web shells under the web root or altered Perl/CGI scripts.
      • Identity side (Windows): Correlate Event IDs 4624/4625 and 4768/4769 for the ICS bind account from unexpected source IPs, plus 4720/4728 (account creation, group changes), against the timing of appliance anomalies.

    Classification under NIS2 and CRA

    Rule-based classification from exploitation status and severity. It does not replace a case-by-case assessment.

    NIS2

    NIS2 is EU Directive (EU) 2022/2555 to raise the level of cybersecurity across the Union. It substantially broadens obligations compared with the first NIS directive: more sectors, mandatory risk management, staged reporting duties and personal accountability of senior management.

    Read in glossary
    Actively exploited: treat the vulnerability as a priority in vulnerability handling under Art. 21(2)(e) NIS2. If it is exploited in your environment, check the reporting obligation under Art. 23 (early warning within 24 hours).
    CRA

    The CRA is EU Regulation (EU) 2024/2847 setting horizontal cybersecurity requirements for „products with digital elements“ — from industrial controllers and software to connected consumer devices. For the first time manufacturers must ensure security across the entire product lifecycle, handle vulnerabilities and provide security updates.

    Read in glossary
    Since 11.09.2026, manufacturers of affected products with digital elements must report actively exploited vulnerabilities under Art. 14 CRA, with an early warning within 24 hours via ENISA's single reporting platform.
    ISO/IEC 27001

    ISO/IEC 27001 is the internationally leading standard for an information security management system (ISMS). It describes a risk-based, process-oriented framework to systematically plan, implement, review and improve information security.

    Read in glossary
    Control A.8.8, management of technical vulnerabilities: assess relevance to your systems, plan remediation and keep evidence.

    Description

    Authentication bypass by spoofing in ICS before version 25.1.3.0 allows a remote unauthenticated attacker to execute arbitrary commands. This does not impact ICS version 22.7R2.14 or prior.

    Source: BSI CSAF, BSI WID Portal, cvelistv5, NVD (NIST), ivanti_bulletin, CISA KEV Catalog

    Affected products

    The following versions are affected. Older releases of the same product line are also vulnerable unless stated otherwise.

    Affected products
    VendorProductAffected versionsFixed in
    IvantiConnect Secure
    • < 22.7R2.14
    • < 22.8R2.5
    • < 25.1.1.2
    • < 25.1.3.0
    • < 25.1.3.1
    • 22.7R2.14
    • 22.8R2.5
    • 25.1.1.2
    • 25.1.3.0
    • 25.1.3.1
    ivanticonnect_secure
    • 22.8
    • 25.1.0.0 – < 25.1.1.2
    • 25.1.2.0 – < 25.1.3.0
    • —
    • 25.1.1.2
    • 25.1.3.0

    Weakness classes (CWE)

    • CWE-290Authentication Bypass by Spoofing

      Base

      This attack-focused weakness is caused by incorrectly implemented authentication schemes that are subject to spoofing attacks.

      Entry at MITRE CWE-290

    Public exploit references

    Publicly reported proof-of-concepts, exploit modules and detection templates for this vulnerability. NEOSEC links to the original sources only and does not provide any exploit code.

    Public exploit references
    SourceReferenceMaturityPublished
    CISA KEV CatalogCISA Known Exploited Vulnerability (opens in a new tab)cisa.govactively exploited (KEV)
    PoC-in-GitHub (nomi-sec)ivanti-cve-2026-104935-check (opens in a new tab)github.comPoC (publicly reported)reported, not verified
    PoC-in-GitHub (nomi-sec)CVE-2026-104935-Proof-of-concept (opens in a new tab)github.comPoC (publicly reported)reported, not verified

    References & sources

    • hub.ivanti.coms/article/Security-Advisory-Ivanti-Connect-Secure-CVE-2026-1049…
    • cisa.govknown-exploited-vulnerabilities-catalog?field_cve=CVE-2026-1049…government-resource

    Reanalysis & status changes

    Chronological NVD audit events for this CVE — reanalyses, CVSS updates, CPE diffs.

    1. Initial Analysisnvd@nist.gov

      • CPE Configuration: after OR *cpe:2.3:a:ivanti:connect_secure:*:*:*:*:*:*:*:* versions from (including) 25.1.0.0 up to (excluding) 25.1.1.2 *cpe:2.3:a:ivanti:connect_secure:*:*:*:*:*:*:*:* versions from (including) 25.1.2.0 up to (excluding) 25.1.3.0 *cpe:2.3:a:ivanti:connect_secure:22.8:r2:*:*:*:*:*:* *cpe:2.3:a:ivanti:connect_secure:22.8:r2.1:*:*:*:*:*:* *cpe:2.3:a:ivanti:connect_secure:22.8:r2.2:*:*:*:*:*:* *cpe:2.3:a:ivanti:connect_secure:22.8:r2.3:*:*:*:*:*:* *cpe:2.3:a:ivanti:connect_secure:22.8:r2.4:*:*:*:*:*:*
      • Reference Type: after CISA-ADP: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-104935 Types: US Government Resource
      • Reference Type: after ivanti: https://hub.ivanti.com/s/article/Security-Advisory-Ivanti-Connect-Secure-CVE-2026-104935 Types: Vendor Advisory

    2. CVE CISA KEV Update9119a7d8-5eab-497f-8521-727c672e3725

      • Date Added: after 2026-10-13
      • Due Date: after 2026-10-13
      • Required Action: after 2026-10-13
      • Vulnerability Name: after 2026-10-13

    3. New CVE Received3c1d8aa1-5a33-4ea4-8992-aadd6440af75

      • Description: after Authentication bypass by spoofing in ICS before version 25.1.3.0 allows a remote unauthenticated attacker to execute arbitrary commands. This does not impact ICS version 22.7R2.14 or prior.
      • CVSS V3.1: after AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:L
      • CWE: after CWE-290
      • Affected: after New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/104xxx/CVE-2026-104935.json">CVE-2026-104935</a>

    4. CVE Modified134c704f-9b21-4f2e-91b3-4a467353bcc0

      • Reference: after https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2026-104935
      • SSVC: after {"id":"CVE-2026-104935","role":"CISA Coordinator","options":[{"exploitation":"active"},{"automatable":"yes"},{"techni…

    Linked advisories