# CVE-2026-126156: Fortinet FortiMail authorization bypass in IBE recipient account

Source: https://junglewise.ai/threats/cve-2026-126156-a-authorization-bypass-through-user-controlled-key-vulnerability  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-11. Updated: 2026-11-11  
License: CC BY 4.0 with a link back

CVE-2026-126156 · Severity: critical · CVSS 9.1 · Published 2026-11-11

FortiMail is an email security gateway that protects organizations from threats. An unauthenticated attacker can bypass authentication controls and take over any IBE (Identity-Based Encryption) recipient account by sending crafted HTTP requests, potentially exposing sensitive emails and compromising email communications.

Technologies: [Fortinet FortiMail](https://junglewise.ai/threats/technologies/fortimail). Vendors: [Fortinet](https://junglewise.ai/threats/vendors/fortinet).

## Quick answers

**Is CVE-2026-126156 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-126156 being exploited in the wild.

**How severe is CVE-2026-126156?** Critical severity, with a CVSS score of 9.1, published 11 November 2026.

**Which products and versions are affected?** Fortinet FortiMail 8.0.0 through 8.0.1, 7.6.0 through 7.6.6, 7.4.0 through 7.4.8, 7.2 all versions.

**Is there a fix for CVE-2026-126156?** Yes: fixed in FortiMail 8.0.2 or above, 7.6.7 or above, 7.4.9 or above; FortiMail 7.2 all versions require migration to a fixed release. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-126156 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-126156?** Check whether you run Fortinet FortiMail at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- Fixed in FortiMail 8.0.2 or above, 7.6.7 or above, 7.4.9 or above; FortiMail 7.2 all versions require migration to a fixed release

## Technical details

An authorization bypass vulnerability through user-controlled key (CWE-639) in the FortiMail API allows unauthenticated remote attackers to assume control of arbitrary IBE recipient accounts via malicious HTTP requests. The vulnerability affects multiple versions across FortiMail 8.0, 7.6, 7.4, and 7.2 branches. Successful exploitation requires only network access and crafted request payloads, with no authentication or user interaction needed.

## Affected products

- Fortinet FortiMail 8.0.0 through 8.0.1, 7.6.0 through 7.6.6, 7.4.0 through 7.4.8, 7.2 all versions

## Timeline

- 2026-11-10: disclosed
- 2026-10-05: patched: FortiMail Cloud remediated

## References

- [https://fortiguard.fortinet.com/psirt/FG-IR-26-208](https://fortiguard.fortinet.com/psirt/FG-IR-26-208)

## Related threats

- [Fortinet FortiMail SQL injection](https://junglewise.ai/threats/cve-2026-126263-a-improper-neutralization-of-special-elements-used-in-an-sql)
- [Fortinet FortiMail argument injection in administrative interface](https://junglewise.ai/threats/cve-2026-126169-a-improper-neutralization-of-argument-delimiters-in-a-command)
- [Fortinet FortiMail argument injection in administrative interface](https://junglewise.ai/threats/cve-2026-126168-a-improper-neutralization-of-argument-delimiters-in-a-command)
- [Fortinet FortiMail command injection in admin GUI](https://junglewise.ai/threats/cve-2026-126167-a-improper-neutralization-of-special-elements-used-in-a-command)
- [Fortinet FortiMail argument injection in admin interface](https://junglewise.ai/threats/cve-2026-126166-a-improper-neutralization-of-argument-delimiters-in-a-command)