CVE-2020-15955 - Vulnerability Details - OpenCVE

Description

In s/qmail through 4.0.07, an active MitM can inject arbitrary plaintext commands into a STARTTLS encrypted session between an SMTP client and s/qmail. This allows e-mail messages and user credentials to be sent to the MitM attacker.

Published: 2021-08-17

Score: 5.9 Medium

EPSS: < 1% Very Low

KEV: No

Impact:

Action:

Analysis

Analysis and contextual insights are available on OpenCVE Cloud.

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

n/a

n/a

affected

Version	Status	Constraints
`n/a`	affected	—

Configuration 1 [-]

cpe:2.3:a:fehcom:s\/qmail:*:*:*:*:*:*:*:*

No data.

No data available yet.

Remediation

No vendor fix or workaround currently provided.

Additional remediation guidance may be available on OpenCVE Cloud.

Tracking

Sign in to view the affected projects.

Advisories

Source	ID	Title
EUVD	EUVD-2020-7926	In s/qmail through 4.0.07, an active MitM can inject arbitrary plaintext commands into a STARTTLS encrypted session between an SMTP client and s/qmail. This allows e-mail messages and user credentials to be sent to the MitM attacker.

No CVSS v4.0

Attack Vector Network

Attack Complexity High

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact None

Availability Impact None

User Interaction None

No CVSS v3.0

Access Vector Network

Access Complexity Medium

Authentication None

Confidentiality Impact Partial

Integrity Impact None

Availability Impact None

This CVE is not in the KEV list.

The EPSS score is 0.0095.

Key SSVC decision points have not yet been added.

References

Link	Providers
https://nostarttls.secvuln.info/
https://www.fehcom.de/sqmail/sqmail.html

History

No history.

Subscriptions

Fehcom S\/qmail

MITRE

Status: PUBLISHED

Assigner: mitre

Published: 2021-08-17T17:12:09.000Z

Updated: 2024-08-04T13:30:23.461Z

Reserved: 2020-07-27T00:00:00.000Z

Link: CVE-2020-15955

Vulnrichment

No data.

NVD

Status : Modified

Published: 2021-08-17T18:15:06.990

Modified: 2026-06-17T02:57:29.223

Link: CVE-2020-15955

Redhat

No data.

OpenCVE Enrichment

No data.

Weaknesses

CWE-77
Improper Neutralization of Special Elements used in a Command ('Command Injection')

{"containers": {"cna": {"affected": [{"product": "n/a", "vendor": "n/a", "versions": [{"status": "affected", "version": "n/a"}]}], "descriptions": [{"lang": "en", "value": "In s/qmail through 4.0.07, an active MitM can inject arbitrary plaintext commands into a STARTTLS encrypted session between an SMTP client and s/qmail. This allows e-mail messages and user credentials to be sent to the MitM attacker."}], "problemTypes": [{"descriptions": [{"description": "n/a", "lang": "en", "type": "text"}]}], "providerMetadata": {"dateUpdated": "2021-08-17T17:12:09.000Z", "orgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca", "shortName": "mitre"}, "references": [{"tags": ["x_refsource_MISC"], "url": "https://www.fehcom.de/sqmail/sqmail.html"}, {"tags": ["x_refsource_MISC"], "url": "https://nostarttls.secvuln.info/"}], "x_legacyV4Record": {"CVE_data_meta": {"ASSIGNER": "cve@mitre.org", "ID": "CVE-2020-15955", "STATE": "PUBLIC"}, "affects": {"vendor": {"vendor_data": [{"product": {"product_data": [{"product_name": "n/a", "version": {"version_data": [{"version_value": "n/a"}]}}]}, "vendor_name": "n/a"}]}}, "data_format": "MITRE", "data_type": "CVE", "data_version": "4.0", "description": {"description_data": [{"lang": "eng", "value": "In s/qmail through 4.0.07, an active MitM can inject arbitrary plaintext commands into a STARTTLS encrypted session between an SMTP client and s/qmail. This allows e-mail messages and user credentials to be sent to the MitM attacker."}]}, "problemtype": {"problemtype_data": [{"description": [{"lang": "eng", "value": "n/a"}]}]}, "references": {"reference_data": [{"name": "https://www.fehcom.de/sqmail/sqmail.html", "refsource": "MISC", "url": "https://www.fehcom.de/sqmail/sqmail.html"}, {"name": "https://nostarttls.secvuln.info/", "refsource": "MISC", "url": "https://nostarttls.secvuln.info/"}]}}}, "adp": [{"providerMetadata": {"orgId": "af854a3a-2127-422b-91ae-364da2661108", "shortName": "CVE", "dateUpdated": "2024-08-04T13:30:23.461Z"}, "title": "CVE Program Container", "references": [{"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://www.fehcom.de/sqmail/sqmail.html"}, {"tags": ["x_refsource_MISC", "x_transferred"], "url": "https://nostarttls.secvuln.info/"}]}]}, "cveMetadata": {"assignerOrgId": "8254265b-2729-46b6-b9e3-3dfca2d5bfca", "assignerShortName": "mitre", "cveId": "CVE-2020-15955", "datePublished": "2021-08-17T17:12:09.000Z", "dateReserved": "2020-07-27T00:00:00.000Z", "dateUpdated": "2024-08-04T13:30:23.461Z", "state": "PUBLISHED"}, "dataType": "CVE_RECORD", "dataVersion": "5.1"}

{"affected": [{"affectedData": [{"product": "n/a", "vendor": "n/a", "versions": [{"status": "affected", "version": "n/a"}]}], "source": "cve@mitre.org"}], "configurations": [{"nodes": [{"cpeMatch": [{"criteria": "cpe:2.3:a:fehcom:s\\/qmail:*:*:*:*:*:*:*:*", "matchCriteriaId": "0C54C1F3-0745-4427-96E1-C67B75B15B5D", "versionEndIncluding": "4.0.07", "vulnerable": true}], "negate": false, "operator": "OR"}]}], "cveTags": [], "descriptions": [{"lang": "en", "value": "In s/qmail through 4.0.07, an active MitM can inject arbitrary plaintext commands into a STARTTLS encrypted session between an SMTP client and s/qmail. This allows e-mail messages and user credentials to be sent to the MitM attacker."}, {"lang": "es", "value": "En s/qmail versiones hasta 4.0.07, un MitM activo puede inyectar comandos de texto plano arbitrario en una sesi\u00f3n cifrada STARTTLS entre un cliente SMTP y s/qmail. Esto permite enviar mensajes de correo electr\u00f3nico y credenciales de usuario al atacante MitM."}], "id": "CVE-2020-15955", "lastModified": "2026-06-17T02:57:29.223", "metrics": {"cvssMetricV2": [{"acInsufInfo": false, "baseSeverity": "MEDIUM", "cvssData": {"accessComplexity": "MEDIUM", "accessVector": "NETWORK", "authentication": "NONE", "availabilityImpact": "NONE", "baseScore": 4.3, "confidentialityImpact": "PARTIAL", "integrityImpact": "NONE", "vectorString": "AV:N/AC:M/Au:N/C:P/I:N/A:N", "version": "2.0"}, "exploitabilityScore": 8.6, "impactScore": 2.9, "obtainAllPrivilege": false, "obtainOtherPrivilege": false, "obtainUserPrivilege": false, "source": "nvd@nist.gov", "type": "Primary", "userInteractionRequired": false}], "cvssMetricV31": [{"cvssData": {"attackComplexity": "HIGH", "attackVector": "NETWORK", "availabilityImpact": "NONE", "baseScore": 5.9, "baseSeverity": "MEDIUM", "confidentialityImpact": "HIGH", "integrityImpact": "NONE", "privilegesRequired": "NONE", "scope": "UNCHANGED", "userInteraction": "NONE", "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N", "version": "3.1"}, "exploitabilityScore": 2.2, "impactScore": 3.6, "source": "nvd@nist.gov", "type": "Primary"}]}, "published": "2021-08-17T18:15:06.990", "references": [{"source": "cve@mitre.org", "tags": ["Technical Description", "Third Party Advisory"], "url": "https://nostarttls.secvuln.info/"}, {"source": "cve@mitre.org", "tags": ["Patch", "Release Notes", "Vendor Advisory"], "url": "https://www.fehcom.de/sqmail/sqmail.html"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Technical Description", "Third Party Advisory"], "url": "https://nostarttls.secvuln.info/"}, {"source": "af854a3a-2127-422b-91ae-364da2661108", "tags": ["Patch", "Release Notes", "Vendor Advisory"], "url": "https://www.fehcom.de/sqmail/sqmail.html"}], "sourceIdentifier": "cve@mitre.org", "vulnStatus": "Modified", "weaknesses": [{"description": [{"lang": "en", "value": "CWE-77"}], "source": "nvd@nist.gov", "type": "Primary"}]}