CVE-2026-11970

Executive Summary

CVE-2026-11970 is a locally exploitable security-control bypass in Forcepoint One Endpoint (F1E) for macOS, affecting builds before v26.04.5758. According to the NVD description, a standard (non-admin) macOS user can disable the Forcepoint One Endpoint SafariExtension, which removes data-loss-prevention (DLP) inspection from the Safari browser channel and allows sensitive data to leave the endpoint undetected. The flaw is rooted in improper handling of an exceptional condition (CWE-754) — the DLP agent fails to enforce protection when the Safari extension is no longer enabled. No CVSS score has been assigned, no public exploit code is known, the vulnerability is not listed in CISA KEV, and EPSS places it in the 2.1st percentile of known exploited-CVE likelihood (0.00119). Patch confidence is 0/4, meaning no tracked source has confirmed an available fix despite the version reference in the description.

Technical Analysis

The vulnerability resides in the Forcepoint One Endpoint (F1E) macOS DLP agent and its associated Safari extension. The NVD description is terse and discloses no function names, file paths, API endpoints, or configuration keys. The analysis below is therefore constrained to the vulnerability class and the observable behavior stated in the description.

Forcepoint One Endpoint is an endpoint DLP product; on macOS, a component of its browser inspection capability is delivered as a Safari extension. For DLP to protect web-based data egress through Safari, the extension must be present, loaded, and performing content inspection on the browser session. The security control therefore has an architectural dependency on the extension's runtime state.

The flaw is categorized as CWE-754 — Improper Check for Unusual or Exceptional Conditions. In this case, the "unusual or exceptional condition" is the Safari extension being disabled, unloaded, or removed by the local user. The NVD description states that a normal, non-admin user can disable the extension. Standard macOS user accounts are normally able to disable per-user Safari extensions from within Safari's settings without elevated privileges. The vulnerable F1E agent apparently does not adequately check for this exceptional state at enforcement time and fails to activate a compensating control. Expected compensating behaviors would include: blocking Safari traffic until the extension is re-enabled, terminating or quarantining the browser session, alerting the management console, or preventing the disablement in the first place. Instead, the agent allows the browser to continue operating without DLP inspection — a fail-open condition.

The attack surface is entirely local and does not involve a network-exposed service. No authentication bypass, memory corruption, or privilege escalation is claimed; the actor only needs a valid, unprivileged macOS account on a managed endpoint. The affected channel is the Safari DLP path; other DLP channels (email, USB storage, cloud apps, etc.) may remain operational, but browser-based exfiltration is unprotected on vulnerable builds.

Because the description offers no implementation-level detail, it is not possible to specify which agent process performs the state check, how the extension communicates with the agent, or which log source captures the disablement event. Detection and remediation efforts must therefore rely on general macOS endpoint telemetry and on the vendor's product documentation for the F1E agent's internal event schema.

Exploitation Scenarios

No public PoC or exploit code is available for CVE-2026-11970; the attack chain below is inferred from the vulnerability class and the NVD description, not from observed in-the-wild activity.

1. Reconnaissance / target identification: The actor possesses local access to a macOS endpoint as an unprivileged user, either as a malicious insider or through prior initial access (e.g., phishing, credential theft). The actor identifies that Forcepoint One Endpoint DLP is installed — typically visible via the F1E menu-bar agent and by enumerating the Safari extensions list. No admin rights, kernel access, or network scanning are required. The actor does not need to know the vulnerable build number; any pre-v26.04.5758 F1E macOS install is a candidate.

2. Triggering the flaw: The actor opens Safari Settings (Extensions pane) and disables the Forcepoint One Endpoint SafariExtension. macOS permits standard users to toggle per-user extensions, and the vulnerable F1E agent fails to correctly handle this exceptional condition (CWE-754). Because the agent does not detect, block, or remediate the state change, the browser DLP inspector is removed from the session.

3. Payload / execution method at the class level: There is no exploit payload. The technique is local state manipulation — disabling a security extension — which corresponds to ATT&CK T1562.001 (Impair Defenses: Disable or Modify Tools). The execution is limited to a user-level configuration change in the browser; no command injection, code execution, or privilege boundary crossing is involved.

4. Post-exploitation impact: With the extension disabled, the actor uses Safari to exfiltrate sensitive data: webmail attachments, uploads to cloud storage or web applications, data pasted into browser-based forms, and other HTTP/HTTPS channels. These transactions are no longer subject to DLP content inspection, so they bypass alerts, policy enforcement, and audit logging associated with the F1E browser channel. If the F1E agent also fails to report the extension's disabled state to the Forcepoint management console, the condition may persist for an extended dwell time until a manual check occurs.

The practical impact is equivalent to silently uninstalling the browser DLP filter on an otherwise managed host. The bypass is limited to Safari-originated traffic; other DLP-protected vectors remain intact unless the actor combines this with additional weaknesses.

Impact Assessment

• Business impact: Loss of DLP assurance for macOS endpoints; inability to demonstrate regulatory compliance for data-in-motion protections (GDPR, HIPAA, PCI-DSS, IP protection). A non-admin user neutralizing a security control undermines the "trusted endpoint" model and may invalidate audit assertions.
• Confidentiality: Directly impacted. The DLP control exists specifically to prevent unauthorized egress of sensitive data; the bypass opens a clean, unmonitored data path through Safari.
• Integrity: No integrity impact is described by the NVD.
• Availability: Low. Disabling the extension does not imply a denial of service to the host; only the DLP inspection function is lost.
• Affected systems: All F1E macOS deployments earlier than v26.04.5758. The Windows and Linux channels of Forcepoint One Endpoint are not in scope of this CVE based on the description.
• Blast radius: Enterprise macOS fleets using Forcepoint One Endpoint. The vulnerability is local, so it is not directly exploitable over the network; the blast radius is organizational — any standard user with access to a vulnerable endpoint can bypass DLP at will, with no technical barriers.
• CVSS: N/A — no score has been officially assigned, so severity cannot be stated numerically. Contextual severity should be assessed as medium-to-high for regulated environments given the low exploitation complexity and the high confidentiality impact.
• EPSS: 0.00119 (2.1st percentile) — the community model currently rates this CVE as unlikely to be exploited in the wild in the near term. This is a likelihood estimate, not a statement about impact.
• CISA KEV: Not listed; there is no CISA-mandated remediation deadline associated with this CVE.

Detection Guidance

Detection is complicated by the absence of public technical artifacts (no file paths, process names, or log identifiers are disclosed for the F1E agent). The rules below focus on two observable signals: (a) the local state change of the Safari extension being disabled, and (b) the downstream consequence — abnormally large or policy-violating egress from hosts that run the F1E agent. All rules require tuning against the organization's actual F1E and macOS telemetry schema.

Sigma Rule

title: Forcepoint One Endpoint SafariExtension Disabled on macOS
id: a1b2c3d4-0000-0000-0000-000000001197
status: experimental
description: Detects the disabling of the Forcepoint One Endpoint SafariExtension on macOS, which may indicate attempted DLP bypass (CVE-2026-11970).
references:
    - https://nvd.nist.gov/vuln/detail/CVE-2026-11970
author: Valterit Threat Intelligence
date: 2026/04/20
tags:
    - attack.defense_evasion
    - attack.t1562.001
    - cve.2026.11970
logsource:
    product: macos
    category: process_creation
detection:
    selection_safari:
        Image|endswith: '/Safari'
    selection_extensions:
        CommandLine|contains:
            - 'Extensions'
            - 'extensions'
    condition: selection_safari and selection_extensions
falsepositives:
    - Authorized administration of Safari extensions by IT staff
level: medium

Note: If the environment has access to F1E agent application logs, extend or replace this rule with a logsource of category: application matching agent-side events that reference "SafariExtension" together with "disabled", "unloaded", "missing", or "removed".

YARA Rule

rule CVE_2026_11970_Forcepoint_SafariExtension_Bypass
{
    meta:
        author = "Valterit Threat Intelligence"
        description = "Detects log or configuration artifacts referencing the Forcepoint One Endpoint SafariExtension and a disabled/unloaded state (CVE-2026-11970)"
        reference = "https://nvd.nist.gov/vuln/detail/CVE-2026-11970"
        date = "2026-04-20"
    strings:
        $fp = "Forcepoint One Endpoint" ascii wide nocase
        $ext = "SafariExtension" ascii wide nocase
        $s1 = "disabled" ascii wide nocase
        $s2 = "unloaded" ascii wide nocase
        $s3 = "missing" ascii wide nocase
        $s4 = "removed" ascii wide nocase
    condition:
        $fp and $ext and 1 of ($s*)
}

Suricata IDS Rule

The extension toggle itself is a local OS/browser event and is not directly observable on the wire. The following rule detects the exfiltration signature that the bypass enables: bulk multipart uploads over HTTP from managed macOS hosts. Threshold tuning is mandatory.

alert http any any -> any any (msg:"CVE-2026-11970 Forcepoint F1E DLP Bypass - Anomalous Multipart Upload (Potential Data Exfiltration)"; flow:established,to_server; content:"POST"; http_method; content:"multipart/form-data"; http_client_body; threshold:type threshold, track by_src, seconds 120, count 8; sid:2026119701; rev:1; metadata:cve CVE-2026-11970;)

Elastic Detection

sequence by host.id with maxspan=10m
  [ process where process.name == "Safari" and process.args : ("*Extensions*", "*extensions*") ]
  [ file where event.action in ("modify", "write") and file.path : "*Safari*Extension*" ]

This EQL sequence correlates a Safari process invoking the Extensions settings surface with a subsequent modification to Safari extension-related files. If the environment captures F1E agent logs, the following EQL can be appended or used instead:

event.category == "process" and process.name : "*forcepoint*" and message : "*SafariExtension*" and message : ("*disabled*", "*unloaded*", "*missing*")

Splunk SPL Query

(index=macos OR sourcetype=osx:syslog OR sourcetype=macos:unified)
  ("Forcepoint One Endpoint" OR "SafariExtension")
  (disabled OR unloaded OR missing OR removed)
| stats count min(_time) max(_time) values(sourcetype) by host, user, source
| where count > 0

Supplement with an egress-based query to spot the downstream effect of the bypass:

(index=proxy OR index=firewall) action=allowed src_user!=*svc* OR src_ip=*
| stats sum(bytes_out) as egress by src_ip, user, dest_domain, _time
| where egress > 100000000
| sort - egress

Wazuh OSSEC Rule

<group name="forcepoint,dlp_bypass,">
  <rule id="100971" level="12">
    <decoded>
    <match>Forcepoint One Endpoint|SafariExtension</match>
    <regex>disabled|unloaded|missing|removed</regex>
    <description>Forcepoint One Endpoint Safari extension disabled - possible DLP bypass (CVE-2026-11970)</description>
    <mitre>
      <id>T1562</id>
    </mitre>
    <group>defense_evasion,</group>
  </rule>
</group>

Mitigation & Patch Guidance

Patch confidence: 0/4 — no tracked source confirms an available patch. The NVD description references F1E Mac OS v26.04.5758 as the version boundary (vulnerable "before" that build), which implies a fixed build, but no vendor advisory or patch artifact has been observed by the tracked sources used in this report. Treat the upgrade path as provisional until Forcepoint publishes an official advisory.

1. Immediate mitigations

• Deploy a macOS configuration profile via MDM (e.g., Jamf, Intune, Mosyle) that manages Safari extensions and restricts standard users from toggling extension state. MDM-enforced extension management is the most direct compensating control for this CVE.
• If the F1E product exposes a tamper-protection or integrity-monitoring mode, enable it so the agent detects and alerts when its Safari extension is unloaded.
• Add a network-layer compensating control: route outbound web traffic through a secure web gateway or TLS-inspecting proxy that applies DLP policy independent of the endpoint agent. This neutralizes the Safari channel even when the local extension is disabled.
• Instruct IT/SOC staff to manually verify Safari extension status on sensitive macOS endpoints during routine audits, and to re-enable the extension if found disabled.

2. Patch / upgrade steps

• Subscribe to Forcepoint's security advisory and support portal notifications. Confirm with the vendor that F1E Mac OS v26.04.5758 (or a later build) addresses CVE-2026-11970 before deploying.
• Stage the upgrade in a pilot group of macOS endpoints, verify that the SafariExtension remains enabled after upgrade and that DLP policy applies to Safari traffic, then roll out to the fleet.
• Do not rely solely on the EPSS score (0.00119) to deprioritize patching; the low likelihood estimate reflects current exploit activity, not residual risk in regulated environments.

3. Long-term hardening

• Apply least-privilege principles to macOS standard accounts and audit entitlement grants; a non-admin user should never be able to silently neutralize a security control.
• Deploy an EDR/endpoint detection product with macOS Endpoint Security Framework support so that browser extension state changes, agent process tampering, and preference-file modifications are captured in a central SIEM.
• Validate the DLP deployment periodically by attempting to disable each browser extension from a standard user account; treat any successful disablement as a finding and remediate via configuration policy.
• Diversify DLP coverage: combine endpoint DLP with CASB (cloud access security broker), data classification, and user behavior analytics so that no single browser channel is the sole control point.

References

• NVD entry for CVE-2026-11970: https://nvd.nist.gov/vuln/detail/CVE-2026-11970
• MITRE CWE-754 — Improper Check for Unusual or Exceptional Conditions: https://cwe.mitre.org/data/definitions/754.html
• MITRE ATT&CK — T1562.001 Impair Defenses: Disable or Modify Tools: https://attack.mitre.org/techniques/T1562/001/
• FIRST EPSS (CVE-2026-11970 score context): https://www.first.org/epss/
• CISA Known Exploited Vulnerabilities Catalog (CVE-2026-11970 is NOT listed): https://www.cisa.gov/known-exploited-vulnerabilities-catalog

No vendor advisory, researcher blog, or threat-actor campaign references were available in the provided data. No exploit-in-the-wild evidence or PoC code is currently known for CVE-2026-11970.