Vulnerability in Froxlor
CVE-2026-100718
Froxlor through 2.3.10 does not enforce the mail.allow_external_domains policy in the EmailSender.add API command. When an administrator has enabled the allowed-sender feature but disabled external allowed-sender domains (mail.enable_allow_sender = 1, mail.allow_external_domains = 0), an authenticated customer with API access can still use EmailSender.add to register an arbitrary external sender address for their mailbox, which is stored despite the policy. This creates a bypass between the UI/administrator configuration and the API, and — where the generated mail configuration consumes the allowed-sender table — allows a customer to authorize sender identities outside their hosted domains, facilitating sender spoofing. Fixed in 2.3.12.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.1 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:H/A:N.
EPSS exploit prediction
EPSS: 0.002 (8.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 8th percentile — 8.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: 0.000
Affected products
Weakness classification (CWE)
References
- GitHub Security Advisory (GHSA-m9j6-9856-68xf) (vendor-advisory)
- VulnCheck Advisory: Froxlor before 2.3.12 Authentication Bypass via EmailSender.add (third-party-advisory)
Frequently asked questions
- What is CVE-2026-100718?
- CVE-2026-100718 is a high-severity vulnerability in Froxlor, classified under Incorrect Default Permissions. CVSS score: 7.1/10. Published 2026-09-26.
- How severe is CVE-2026-100718?
- High severity. CVSS v3 base score is 7.1 out of 10.