CVE-2026-42006
Estado: ModificadaMedia (4.3)—
An attacker can cause uncontrolled memory usage with excessive bracing over IMAP. The fix in CVE-2026-27857 was incomplete, only blocking one way of doing this, so there was still another way left open. In particular, the fix was for closing braces, but you could still use open braces to bypass the limit. Using excessive bracing, attacker can cause memory usage up to configured memory limit. Install fixed version, or configure vsz_limit for imap process to low value. No publicly available exploits are known.
CVSS
- Versión: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
- Puntuación base: 4.3
Probabilidad de explotación (EPSS)
- Probabilidad de explotación en los próximos 30 días: 0.82%
- Percentil entre todas las CVEs puntuadas: 56
- Fecha de la puntuación: 6/10/2026
EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).
Tecnologías afectadas (2)
CWE
- CWE-400
- CWE-770
Referencias
- https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0002.json
- https://access.redhat.com/errata/RHSA-2026:41905
- https://access.redhat.com/errata/RHSA-2026:41988
- https://access.redhat.com/errata/RHSA-2026:42091
- https://access.redhat.com/errata/RHSA-2026:44355
- https://access.redhat.com/errata/RHSA-2026:44357
- https://access.redhat.com/errata/RHSA-2026:44373
- https://access.redhat.com/errata/RHSA-2026:46379
- https://access.redhat.com/errata/RHSA-2026:46380
- https://access.redhat.com/errata/RHSA-2026:46381
- https://access.redhat.com/errata/RHSA-2026:46532
- https://access.redhat.com/errata/RHSA-2026:49513
- https://access.redhat.com/security/cve/CVE-2026-42006
- https://bugzilla.redhat.com/show_bug.cgi?id=2476476
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42006.json
JSON original (NVD)
Mostrar
{
"id": "CVE-2026-42006",
"cveTags": [],
"metrics": {
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2026-42006",
"role": "CISA Coordinator",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"version": "2.0.3",
"timestamp": "2026-05-12T15:40:29.845540Z"
}
}
],
"cvssMetricV31": [
{
"type": "Secondary",
"source": "security@open-xchange.com",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 4.3,
"attackVector": "NETWORK",
"baseSeverity": "MEDIUM",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "LOW",
"privilegesRequired": "LOW",
"confidentialityImpact": "NONE"
},
"impactScore": 1.4,
"exploitabilityScore": 2.8
},
{
"type": "Secondary",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"cvssData": {
"scope": "UNCHANGED",
"version": "3.1",
"baseScore": 7.5,
"attackVector": "NETWORK",
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
"integrityImpact": "NONE",
"userInteraction": "NONE",
"attackComplexity": "LOW",
"availabilityImpact": "HIGH",
"privilegesRequired": "NONE",
"confidentialityImpact": "NONE"
},
"impactScore": 3.6,
"exploitabilityScore": 3.9
}
]
},
"affected": [
{
"source": "security@open-xchange.com",
"affectedData": [
{
"vendor": "Open-Xchange GmbH",
"modules": [
"core"
],
"product": "OX Dovecot Pro",
"versions": [
{
"status": "affected",
"version": "0",
"versionType": "semver",
"lessThanOrEqual": "3.0.5"
},
{
"status": "affected",
"version": "0",
"versionType": "semver",
"lessThanOrEqual": "3.1.4"
},
{
"status": "affected",
"version": "0",
"versionType": "semver",
"lessThanOrEqual": "2.4.3"
}
],
"defaultStatus": "unaffected"
}
]
},
{
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"affectedData": [
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:10.2"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 10",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.21-19.el10_2.1",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux_eus:10.0"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 10.0 Extended Update Support",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.21-16.el10_0.2",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:rhel_els:7"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 7 Extended Lifecycle Support",
"versions": [
{
"status": "unaffected",
"version": "1:2.2.36-8.el7_9.2",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:enterprise_linux:8"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.16-8.el8_10",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:rhel_aus:8.4"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.8-9.el8_4.2",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:rhel_eus_long_life:8.4"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.8-9.el8_4.2",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:rhel_aus:8.6"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.16-2.el8_6.2",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:rhel_eus_long_life:8.6"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.16-2.el8_6.2",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:rhel_tus:8.8"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8.8 Telecommunications Update Service",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.16-3.el8_8.2",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:rhel_e4s:8.8"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.16-3.el8_8.2",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:enterprise_linux:9"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.16-18.el9_8.1",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:rhel_e4s:9.2"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.16-8.el9_2.3",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:rhel_e4s:9.4"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.16-11.el9_4.3",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/a:redhat:rhel_eus:9.6"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 9.6 Extended Update Support",
"versions": [
{
"status": "unaffected",
"version": "1:2.3.16-15.el9_6.2",
"lessThan": "*",
"versionType": "rpm"
}
],
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "affected"
},
{
"cpes": [
"cpe:/o:redhat:enterprise_linux:6"
],
"vendor": "Red Hat",
"product": "Red Hat Enterprise Linux 6",
"packageName": "dovecot",
"collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
"defaultStatus": "unknown"
}
]
}
],
"published": "2026-05-12T14:17:04.703",
"references": [
{
"url": "https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0002.json",
"tags": [
"Issue Tracking"
],
"source": "security@open-xchange.com"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:41905",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:41988",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:42091",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:44355",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:44357",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:44373",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:46379",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:46380",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:46381",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:46532",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/errata/RHSA-2026:49513",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://access.redhat.com/security/cve/CVE-2026-42006",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://bugzilla.redhat.com/show_bug.cgi?id=2476476",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
},
{
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42006.json",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c"
}
],
"vulnStatus": "Modified",
"weaknesses": [
{
"type": "Secondary",
"source": "security@open-xchange.com",
"description": [
{
"lang": "en",
"value": "CWE-400"
}
]
},
{
"type": "Secondary",
"source": "0b0ca135-0b70-47e7-9f44-1890c2a1c46c",
"description": [
{
"lang": "en",
"value": "CWE-770"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "An attacker can cause uncontrolled memory usage with excessive bracing over IMAP. The fix in CVE-2026-27857 was incomplete, only blocking one way of doing this, so there was still another way left open. In particular, the fix was for closing braces, but you could still use open braces to bypass the limit. Using excessive bracing, attacker can cause memory usage up to configured memory limit. Install fixed version, or configure vsz_limit for imap process to low value. No publicly available exploits are known."
}
],
"lastModified": "2026-08-03T13:18:24.470",
"configurations": [
{
"nodes": [
{
"negate": false,
"cpeMatch": [
{
"criteria": "cpe:2.3:a:dovecot:dovecot:*:*:*:*:*:*:*:*",
"vulnerable": true,
"matchCriteriaId": "86CE1F3B-DF73-431A-9EC0-491E8969A187",
"versionEndExcluding": "2.4.4"
},
{
"criteria": "cpe:2.3:a:open-xchange:dovecot:*:*:*:*:pro:*:*:*",
"vulnerable": true,
"matchCriteriaId": "28C2DD58-A4B0-4F2C-BC60-F30F380251BC",
"versionEndExcluding": "3.1.5"
}
],
"operator": "OR"
}
]
}
],
"sourceIdentifier": "security@open-xchange.com"
}