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.)
CVE-2026-47085
Score 4.0 from GitHub Security Advisory published 2026-07-16. a secondary CVSS source baseline 4.0; sources differ by 0.0.
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 4.0
- EG Score
- 4.0(high)
- EG Risk
- —
- EPSS
- 8.7%
- KEV
- Not listed
Published
July 16, 2026
Last Modified
July 17, 2026
Advisory Details (2)
Auto-updated Jul 17, 2026Release Notes — Cyrus IMAP 3.12.3 documentation
https://www.cyrusimap.org/imap/download/release-notes/index.htmlCyrus IMAP 3.12.3 Release Notes — Cyrus IMAP 3.12.3 documentation
https://www.cyrusimap.org/3.12/imap/download/release-notes/3.12/x/3.12.3.htmlVendor Advisories for CVE-2026-47085(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 12× in last 7d / 12× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-22 14:08 UTCEPSS rescore
- 2026-07-21 15:24 UTCEPSS rescore
- 2026-07-20 17:08 UTCEPSS rescore
- 2026-07-19 14:31 UTCEPSS rescore
- 2026-07-19 02:36 UTCEG score recompute
- 2026-07-19 02:36 UTCGHSA enrichment
- 2026-07-19 02:29 UTCEPSS rescore
- 2026-07-18 10:04 UTCEPSS rescore
- 2026-07-17 07:06 UTCEG score recompute
- 2026-07-17 07:06 UTCGHSA enrichment
- 2026-07-16 18:49 UTCEG score recompute
- 2026-07-16 18:48 UTCMITRE cvelistV5first tracked
Frequently asked(5)
What is CVE-2026-47085?
When was CVE-2026-47085 disclosed?
Is CVE-2026-47085 actively exploited?
What is the CVSS score of CVE-2026-47085?
How do I remediate CVE-2026-47085?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-47085
Is Your Infrastructure Affected by CVE-2026-47085?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.