CVE-2026-111367

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.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
6.5 MEDIUM
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:L
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: Unknown
Common Weakness Enumeration
References
https://github.com/aaPanel/BillionMail
https://github.com/aaPanel/BillionMail/blob/v4.9/core/internal/service/batch_mail/jwt.go#L98-L123
https://github.com/aaPanel/BillionMail/blob/v4.9/core/manifest/config/config.yaml
https://hackmd.io/@hieuPenguinnn/billionmail-unsubscribe-subscribe-jwt-deterministic-secret-forgery
https://www.vulncheck.com/advisories/billionmail-through-4.9-forgeable-jwts-via-default-signing-key