VULNERABILITY INTELLIGENCE
CVE-2026-47085
CVSS score4 MEDIUM
EPSS probability0.30%
CISA KEVNot currently listed
Published2026-07-16
Last modified2026-10-24
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:L/I:N/A:N
Description
An issue was discovered in cyrus-imapd in Cyrus IMAP through 3.12.2. URLAUTH token forgery can occur via a missing mboxkey. If an attacker knew a folder name on the victim's account for which the victim had never issued an auth URL, they could forge a working URLAUTH token by computing an HMAC-SHA1 value with a predictable key, giving them read access to the mailbox. (URLAUTH is an obscure feature, meaning that the odds of any user actually being susceptible to this attack are very low. Perhaps no public clients use URLAUTH.)
Weakness classification
- cve@mitre.org: CWE-340