dbcve.org
Sling Commons Messaging MailApplication · Apache

CVE-2021-44549

HIGH · 7.4 CVSS v3.1 Published 2021-12-14
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
83/100
Remediation priority · High
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Apache Sling Commons Messaging Mail provides a simple layer on top of JavaMail/Jakarta Mail for OSGi to send mails via SMTPS. To reduce the risk of "man in the middle" attacks additional server identity checks must be performed when accessing mail servers. For compatibility reasons these additional checks are disabled by default in JavaMail/Jakarta Mail. The SimpleMailService in Apache Sling Commons Messaging Mail 1.0 lacks an option to enable these checks for the shared mail session. A user could enable these checks nevertheless by accessing the session via the message created by SimpleMessageBuilder and setting the property mail.smtps.ssl.checkserveridentity to true. Apache Sling Commons Messaging Mail 2.0 adds support for enabling server identity checks and these checks are enabled by default. - https://javaee.github.io/javamail/docs/SSLNOTES.txt - https://javaee.github.io/javamail/docs/api/com/sun/mail/smtp/package-summary.html - https://github.com/eclipse-ee4j/mail/issues/429

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Apache Sling Commons Messaging Mail versions prior to 2.0 lack an option to enable SSL/TLS server identity checks in shared mail sessions, allowing potential man-in-the-middle attacks. While users could manually set mail.smtps.ssl.checkserveridentity to true via SimpleMessageBuilder, version 2.0 adds proper support and enables these checks by default.

MitigationUpgrade to Apache Sling Commons Messaging Mail 2.0 or later where server identity checks are enabled by default, or manually configure mail.smtps.ssl.checkserveridentity=true in the message session.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
Sling Commons Messaging MailApplication
Affected:= 1.0.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed version of Apache Sling Commons Messaging Mail
    Locate the commons-messaging-mail JAR file in your application classpath or build configuration (pom.xml, build.gradle, lib directory) and check the version metadata in the JAR manifest or dependency declaration
    Affected if The version is 1.0.0 or any version prior to 2.0 (such as 1.x releases)
  2. Locate SimpleMessageBuilder configuration
    Search project source code and configuration files for usage of SimpleMessageBuilder class from Apache Sling Commons Messaging Mail
    Affected if SimpleMessageBuilder is used to create mail sessions in your environment
  3. Check for manual server identity verification setting
    Inspect SimpleMessageBuilder configuration code and any associated property files for the setting mail.smtps.ssl.checkserveridentity
    Affected if The property mail.smtps.ssl.checkserveridentity is not set to true, or is absent entirely
  4. Inspect mail session configuration files
    Examine any XML, properties, or OSGi configuration files that define shared mail session settings for mail.smtps.ssl.checkserveridentity
    Affected if Server identity checking is not explicitly enabled (value is not true)

You are affected if Apache Sling Commons Messaging Mail version 1.0.0 (or any pre-2.0 version) is in use AND the mail.smtps.ssl.checkserveridentity property is not explicitly set to true in your configuration.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade to Apache Sling Commons Messaging Mail 2.0 or later where server identity checks are enabled by default, or manually configure mail.smtps.ssl.checkserveridentity=true in the message session.

Recommended fix High confidence

Apache Sling Commons Messaging Mail 2.0.x

  1. Upgrade Apache Sling Commons Messaging Mail from version 1.0.0 to version 2.0.x
  2. In version 2.0, server identity checks are enabled by default for SMTPS connections, providing protection against man-in-the-middle attacks
Caveat May include API changes; review migration notes when upgrading from 1.0.x to 2.0.x

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Sling Commons Messaging Mail Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing3.0 h
  • Review / QA1.0 h
8.0 hours of engineering $1,390
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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-44549 in production — separate from our analysis above.

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What this is

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What belongs here
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  • Version or environment caveats, and links to real fixes
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