CVE-2026-27851

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.

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CVSS v3.1 Score

7.4

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

EPSS — Exploit Prediction

0.0002

Probability of exploitation

0.06%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

Weakness Type (CWE)

CWE-235 CWE-235

Affected Products

Vendor	Product	Versions
dovecot	dovecot	< 2.4.4
open-xchange	dovecot	< 3.1.5

References

Advisories & Patches

https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0002.json

Frequently Asked Questions

What is 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. 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. It has a CVSS v3.1 base score of 7.4 (HIGH).

How severe is CVE-2026-27851? +

CVE-2026-27851 has a CVSS v3.1 score of 7.4 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0002, placing it in the 0th percentile for exploitation probability.

What products are affected by CVE-2026-27851? +

CVE-2026-27851 affects products from dovecot, open-xchange, specifically: dovecot. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2026-27851? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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