VulnerabilityModified

CVE-2026-27851

When safe filter is used with variable expansion, all following pipelines on the same string are incorrectly interpreted as safe too, enabling unsafe data to be unescaped.

CRITICAL 9.1EPSS 0.41%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.41%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

When safe filter is used with variable expansion, all following pipelines on the same string are incorrectly interpreted as safe too, enabling unsafe data to be unescaped. This can enable SQL / LDAP injection attacks when used in authentication. Avoid using safe filter until on fixed version. No publicly available exploits are known.

CVSS 3.1: 9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
EPSS: 0.41% probability · 34th percentile
CISA KEV: Not listed
Weakness: CWE-235, CWE-89
Affected: dovecot/dovecot · open-xchange/dovecot
Source: security@open-xchange.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.