CVE-2026-111367
BillionMail through 4.9 Forgeable JWTs via Default Signing Key
Description
BillionMail through 4.9 contains a hard-coded cryptographic key vulnerability that allows unauthenticated attackers to forge unsubscribe and subscribe-confirm JWTs by computing the key from shipped configuration constants. Attackers can submit forged tokens to /api/unsubscribe, /api/unsubscribe_new, or /api/subscribe/confirm to deactivate any contact or force confirmed subscriptions.
INFO
Published Date :
Oct. 15, 2026, 10:19 p.m.
Last Modified :
Oct. 15, 2026, 10:19 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
Affected Products
The following products are affected by CVE-2026-111367
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 3.1 | MEDIUM | MITRE-CVE | ||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 4.0 | MEDIUM | 83251b91-4cc7-4094-a5c7-464a1b83ea10 | ||||
| CVSS 4.0 | MEDIUM | [email protected] |
Solution
- Update BillionMail to the latest version.
- Change all hard-coded cryptographic keys.
- Rotate all existing JWT tokens.
- Review configuration for sensitive data.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-111367.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-111367 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-111367
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-111367 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-111367 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by [email protected]
Oct. 15, 2026
Action Type Old Value New Value Added Description BillionMail through 4.9 contains a hard-coded cryptographic key vulnerability that allows unauthenticated attackers to forge unsubscribe and subscribe-confirm JWTs by computing the key from shipped configuration constants. Attackers can submit forged tokens to /api/unsubscribe, /api/unsubscribe_new, or /api/subscribe/confirm to deactivate any contact or force confirmed subscriptions. Added CVSS V4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L Added CWE CWE-1394 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/111xxx/CVE-2026-111367.json">CVE-2026-111367</a> Added Reference https://github.com/aaPanel/BillionMail Added Reference https://github.com/aaPanel/BillionMail/blob/v4.9/core/internal/service/batch_mail/jwt.go#L98-L123 Added Reference https://github.com/aaPanel/BillionMail/blob/v4.9/core/manifest/config/config.yaml Added Reference https://hackmd.io/@hieuPenguinnn/billionmail-unsubscribe-subscribe-jwt-deterministic-secret-forgery Added Reference https://www.vulncheck.com/advisories/billionmail-through-4.9-forgeable-jwts-via-default-signing-key