CVE-2026-40016

Attacker can upload a malicious Sieve script over ManageSieve service (or locally) to bypass configured CPU time limits for Sieve up to 130 times of the configured limit. Attacker can use this to degrade server performance and bypass configured CPU time limits for Sieve scripts. Install fixed version, or alternatively prevent direct access to Sieve scripts via ManageSieve or local access. No publicly available exploits are known.

Database specific

{
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/40xxx/CVE-2026-40016.json",
    "cwe_ids": [
        "CWE-400"
    ],
    "unresolved_ranges": [
        {
            "extracted_events": [
                {
                    "last_affected": "2.3.0"
                }
            ],
            "source": "AFFECTED_FIELD"
        }
    ],
    "cna_assigner": "OX"
}

References

Affected packages

Git / github.com/dovecot/core

Affected ranges

Type

GIT

Repo

https://github.com/dovecot/core

Events

Introduced

Fixed

8b687aa65c719e2a0d773eccea84f67c5770fc9a

Database specific

{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "2.4.4"
        }
    ],
    "source": "CPE_RANGE",
    "cpe": "cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:*"
}

Affected versions

1.*

1.1.alpha1

1.1.alpha2

1.1.alpha4

1.1.alpha5

1.1.alpha6

1.1.beta1

1.1.beta10

1.1.beta11

1.1.beta12

1.1.beta13

1.1.beta14

1.1.beta16

1.1.beta2

1.1.beta3

1.1.beta4

1.1.beta5

1.1.beta6

1.1.beta8

1.1.beta9

1.1.rc1

1.1.rc2

1.1.rc3

1.2.alpha1

1.2.alpha2

1.2.alpha3

1.2.alpha4

1.2.alpha5

1.2.beta1

1.2.beta2

1.2.beta3

1.2.beta4

1.2.rc1

2.*

2.0.0

2.0.1

2.0.2

2.0.3

2.0.4

2.0.5

2.0.6

2.0.7

2.0.8

2.0.alpha1

2.0.alpha2

2.0.alpha3

2.0.beta1

2.0.beta2

2.0.beta3

2.0.beta4

2.0.beta5

2.0.beta6

2.0.rc1

2.0.rc2

2.0.rc3

2.0.rc4

2.0.rc5

2.0.rc6

2.1.alpha1

2.1.alpha2

2.1.beta1

2.1.rc1

2.1.rc2

2.1.rc3

2.1.rc4

2.1.rc5

2.1.rc6

2.2.0

2.2.1

2.2.10

2.2.11

2.2.12

2.2.13

2.2.13.rc1

2.2.14

2.2.14.rc1

2.2.15

2.2.16

2.2.16.rc1

2.2.17

2.2.17.rc1

2.2.17.rc2

2.2.18

2.2.19

2.2.19.rc1

2.2.19.rc2

2.2.2

2.2.20

2.2.20.rc1

2.2.3

2.2.4

2.2.5

2.2.6

2.2.7

2.2.8

2.2.9

2.2.alpha1

2.2.beta1

2.2.beta2

2.2.rc1

2.2.rc2

2.2.rc3

2.2.rc4

2.2.rc5

2.2.rc6

2.2.rc7

Database specific

source

"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-40016.json"