# CVE-2026-100718: Froxlor API policy bypass in EmailSender.add

Source: https://junglewise.ai/threats/cve-2026-100718-froxlor-through-2-3-10-does-not-enforce-the-mail-allow-external  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-26. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-100718 · Severity: high · CVSS 7.1 · Published 2026-09-26

Froxlor is a hosting control panel that manages email accounts and sender authentication policies. In versions through 2.3.10, the EmailSender.add API command fails to enforce the administrator's restriction on external sender domains, allowing a customer with API access to register arbitrary sender addresses outside their hosted domains. This enables sender spoofing and circumvents email security policies the administrator explicitly configured.

Technologies: [Froxlor](https://junglewise.ai/threats/technologies/froxlor). Vendors: [Froxlor](https://junglewise.ai/threats/vendors/froxlor).

## Quick answers

**Is CVE-2026-100718 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-100718 being exploited in the wild.

**How severe is CVE-2026-100718?** High severity, with a CVSS score of 7.1, published 26 September 2026.

**Which products and versions are affected?** Froxlor through 2.3.10.

**Is there a fix for CVE-2026-100718?** A patch was published on 2026-09-26: Fixed in version 2.3.12 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-100718 attacked?** It is attacked over the network.

**Am I affected by CVE-2026-100718?** Check whether you run Froxlor 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.

## Technical details

The vulnerability is an authorization bypass (CWE-276) where the EmailSender.add API endpoint does not validate the mail.allow_external_domains policy setting before accepting external sender identities. An authenticated customer with API access can add external sender addresses to their mailbox despite the global policy mail.allow_external_domains = 0 being set. The fix is available in version 2.3.12.

## Affected products

- Froxlor Froxlor through 2.3.10

## Timeline

- 2026-09-26: disclosed
- 2026-09-26: patched: Fixed in version 2.3.12

## References

- [https://github.com/froxlor/froxlor/security/advisories/GHSA-m9j6-9856-68xf](https://github.com/froxlor/froxlor/security/advisories/GHSA-m9j6-9856-68xf)
- [https://www.vulncheck.com/advisories/froxlor-before-2.3.12-authentication-bypass-via-emailsender-add](https://www.vulncheck.com/advisories/froxlor-before-2.3.12-authentication-bypass-via-emailsender-add)

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