How severe is CVE-2016-8652?

CVE-2016-8652 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2016-8652 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 48% (99th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2016-8652?

CVE-2016-8652 affects Dovecot. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2016-8652?

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

When was CVE-2016-8652 published?

CVE-2016-8652 was published on 2017-02-17 and last updated on 2026-06-17.

CVE-2016-8652

CVE-2016-8652 is a medium-severity vulnerability in Dovecot with a CVSS 3.x base score of 5.9. Its EPSS exploit-prediction score of 48% places it in the 99th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 48% (99th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Dovecot
Published: 2017-02-17
Last modified: 2026-06-17

Description

The auth component in Dovecot before 2.2.27, when auth-policy is configured, allows a remote attackers to cause a denial of service (crash) by aborting authentication without setting a username.

Frequently asked questions

What is CVE-2016-8652?: The auth component in Dovecot before 2.2.27, when auth-policy is configured, allows a remote attackers to cause a denial of service (crash) by aborting authentication without setting a username.
How severe is CVE-2016-8652?: CVE-2016-8652 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2016-8652 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 48% (99th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-8652?: CVE-2016-8652 affects Dovecot. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2016-8652?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2016-8652 published?: CVE-2016-8652 was published on 2017-02-17 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:*

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