A origin validation error vulnerability in Fortinet FortiClientMac 7.4.0 through 7.4.7, FortiClientWindows 7.4.0 through 7.4.7…
Affects Fortinet FortiClientMac 7.4.0–7.4.7, FortiClientWindows 7.4.0–7.4.7 and 7.2.0–7.2.14, and FortiClientWindowsPAM per the advisory text. No fixed version is given in the facts.
Written by anthropic/claude-sonnet-5.5 from the sources below. Verify against them.
- Exploited
- No known exploitation
- Fix
- No fix listed
- Who is exposed
- Specific setups only
Do first: Check whether your setup matches what the bug needs. FortiClientMac 7.4.0 through 7.4.7 FortiClientWindows 7.4.0 through 7.4.7 or 7.2.0 through 7.2.14 FortiClientWindowsPAM 7.4.0 through 7.4.7 or 7.2.0 through 7.2.14 The flaw is in a local API endpoint (origin validation error)
- Last modified
- Whether it needs action now or is a reference record, by fixed rules, with why. Last checked is when cve.now last re-read it.What do these mean? →
- Reference
- Last checked
- A 0-100 score for how much a CVE matters across the industry: exploitation, exposure, how widely the software is used, severity and whether a fix exists.What do these mean? →
- 41/100 · provisional
- How many real-world setups can hit the bug, from the vendor's advisory and CISA data. It does not know your setup.What do these mean? →
- Specific setups only
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: no
- Technical impact: total
Summary
Fortinet's FortiClient endpoint software for Mac and Windows (including the Windows PAM component) has an origin validation flaw that lets an attacker run unauthorized code or commands on the affected computer. The attacker can reach it remotely without logging in, but the victim must interact with something, such as visiting a page or clicking a link.
Read the original description
A origin validation error vulnerability in Fortinet FortiClientMac 7.4.0 through 7.4.7, FortiClientWindows 7.4.0 through 7.4.7, FortiClientWindows 7.2.0 through 7.2.14, FortiClientWindowsPAM 7.4.7, FortiClientWindowsPAM 7.2.14 may allow an unauthorized remote attacker to execute unauthorized code or commands. Successful exploitation requires interaction with the victim.
cve.now Index
- Exploitation0/40No signal
- Exposure12/25Specific setups only, reachable over the network without a login
- Reach14/20Affects Fortinet (an enterprise product or network appliance)
- Severity10/10CVSS 9.1, total technical impact per CISA
- No patch5/5No patch listed yet
What would change the score
- Would score about 91 if added to CISA KEV
- Would score about 86 if CISA's SSVC rates exploitation active
What to do
Check whether your setup matches what the bug needs.
FortiClientMac 7.4.0 through 7.4.7 FortiClientWindows 7.4.0 through 7.4.7 or 7.2.0 through 7.2.14 FortiClientWindowsPAM 7.4.0 through 7.4.7 or 7.2.0 through 7.2.14 The flaw is in a local API endpoint (origin validation error)Workaround: The facts list no fix or workaround. Until Fortinet publishes one, the only guidance available is to follow the vendor's advisory and watch for updates.
Check your systems with an agent
Paste this into a coding or ops agent. It checks your systems read-only and reports a table per asset.
Check whether my systems are affected by CVE-2026-121529 (A origin validation error vulnerability in Fortinet FortiClientMac 7.4.0 through 7.4.7, FortiClientWindows 7.4.0 through 7.4.7…), using the cve.now data below. Rules: work read-only. Do not run exploit code, proof-of-concept scripts or scanners that send attack payloads, and do not change any configuration, package, image or deployment. Report findings only. What cve.now has for CVE-2026-121529 (entry last updated 2026-11-10): Affected: - Fortinet FortiClientMac: from 7.4.0, through 7.4.7 - Fortinet FortiClientWindows: from 7.4.0, through 7.4.7; from 7.2.0, through 7.2.14 - Fortinet FortiClientWindowsPAM: versions 7.4.7, 7.2.14 Fixed versions: none listed yet. Conditions (all must be true for the bug to be hit): - FortiClientMac 7.4.0 through 7.4.7 (source: https://fortiguard.fortinet.com/psirt/FG-IR-26-194) - FortiClientWindows 7.4.0 through 7.4.7 or 7.2.0 through 7.2.14 (source: https://fortiguard.fortinet.com/psirt/FG-IR-26-194) - FortiClientWindowsPAM 7.4.0 through 7.4.7 or 7.2.0 through 7.2.14 (source: https://fortiguard.fortinet.com/psirt/FG-IR-26-194) - The flaw is in a local API endpoint (origin validation error) (source: https://fortiguard.fortinet.com/psirt/FG-IR-26-194) Setup: unknown whether the bug needs a non-default feature or setting. Check the advisory. Attacker needs: network access, no login, a user action. CISA KEV: CVE-2026-121529 is not listed as of cve.now's last read. This KEV status is for CVE-2026-121529 only. If you also check another CVE, look up its own KEV status; never assume it from this one. How to check: - Installed software: check what is actually running, not what a repo declares. Read the version from each host, container image and Kubernetes node (the binary's version output, the OS package database, image layers), and check whether the conditions above hold there. Distribution packages may carry a backported fix under an older version number; confirm against the distribution's own advisory. Verify against the linked advisories before concluding, and cite the date you read each one: - https://fortiguard.fortinet.com/psirt/FG-IR-26-194 Do not conclude an asset is unaffected unless you checked it and the evidence covers both its version and the conditions above. If you could not check something, mark it unknown and say what is missing. Report a table with one row per asset and these columns: Asset | Version or build | Status (affected, fixed, not applicable, unknown) | Compensating controls | Exposure (internet-facing, internal, none) | Evidence | Next action. Entry: https://cve.now/CVE-2026-121529 For follow-up questions, use the cve.now MCP server at https://mcp.cve.now/mcp (no authentication), for example get_vulnerability with id CVE-2026-121529.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: total
- Record last updated
- First seen by cve.now
- Posted on X by cve.now
Affected versions
- Fortinet FortiClientMac
From 7.4.0 · through 7.4.7
- Fortinet FortiClientWindows
From 7.4.0 · through 7.4.7; From 7.2.0 · through 7.2.14
- Fortinet FortiClientWindowsPAM
7.4.7, 7.2.14
Evidence 3
Vendor advisory · 1
Establishes: Affected and fixed versions.
- Link
CVE record · 2
Establishes: The identifier and description.
- Record
- Record
Corrections
None so far.
Something wrong on this page? Report an error. Every fix is listed here.
Questions about CVE-2026-121529
Is CVE-2026-121529 being exploited?
It is not in CISA's Known Exploited Vulnerabilities catalog, and CISA's SSVC assessment does not mark exploitation as active. That does not mean it has not been attacked: vendors and researchers can report attacks before CISA lists them. No public exploit code is tracked.Source: cve.now feed data
What does this mean?
A local API endpoint in FortiClient does not properly validate where requests come from (an origin validation error). The advisory says this may allow an unauthorized remote attacker to execute unauthorized code or commands on the endpoint.Source: fortiguard.fortinet.com
Which versions are affected by CVE-2026-121529?
FortiClientMac: from 7.4.0 through 7.4.7. FortiClientWindows: from 7.4.0 through 7.4.7; from 7.2.0 through 7.2.14. FortiClientWindowsPAM: versions 7.4.7, 7.2.14.Source: cve.now feed data
Am I affected, and how do I check?
Listed as affected: FortiClientMac 7.4.0 through 7.4.7, FortiClientWindows 7.4.0 through 7.4.7 and 7.2.0 through 7.2.14, and FortiClientWindowsPAM 7.4.0 through 7.4.7 or 7.2.0 through 7.2.14 (the advisory text gives these ranges for PAM). To compare, check the installed FortiClient version in the application's About or settings page.Source: fortiguard.fortinet.com
How do I fix CVE-2026-121529?
The facts do not name a fixed version or a workaround. Check Fortinet's advisory for the current fix and upgrade guidance.Source: fortiguard.fortinet.com
What if there's no patch?
The facts list no fix or workaround. Until Fortinet publishes one, the only guidance available is to follow the vendor's advisory and watch for updates.Source: fortiguard.fortinet.com