How severe is CVE-2026-61909?

CVE-2026-61909 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2026-61909 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-61909?

CVE-2026-61909 affects Cyrus Imap. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-61909?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2026-61909 published?

CVE-2026-61909 was published on 2026-09-09 and last updated on 2026-09-16.

CVE-2026-61909

CVE-2026-61909 is a low-severity vulnerability in Cyrus Imap with a CVSS 3.x base score of 3.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-420.

Key facts

Severity: Low (CVSS 3.x base score 3.5)
EPSS exploit prediction: 0% (9th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-420
Affected product: Cyrus Imap
Published: 2026-09-09
Last modified: 2026-09-16

Description

An issue was discovered in Cyrus IMAP before 3.12.4. CalDAV/CardDAV multiget bypasses a per-href ACL. An authenticated DAV user with some shared access to another user's calendar or address book could read even unshared events or contacts by including the target hrefs in a calendar-multiget or addressbook-multiget REPORT.

Frequently asked questions

What is CVE-2026-61909?: An issue was discovered in Cyrus IMAP before 3.12.4. CalDAV/CardDAV multiget bypasses a per-href ACL. An authenticated DAV user with some shared access to another user's calendar or address book could read even unshared events or contacts by including the target hrefs in a calendar-multiget or addressbook-multiget REPORT.
How severe is CVE-2026-61909?: CVE-2026-61909 has a CVSS 3.x base score of 3.5, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2026-61909 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (9th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-61909?: CVE-2026-61909 affects Cyrus Imap. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-61909?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2026-61909 published?: CVE-2026-61909 was published on 2026-09-09 and last updated on 2026-09-16.

References

Affected products (1)

cpe:2.3:a:cyrus:imap:*:*:*:*:*:*:*:*

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