dbcve.org
OtrsApplication

CVE-2026-48187

MEDIUM · 5.7 CVSS v3.1 Published 2026-06-01
Fix available
A fix is available. Upgrade to 2026.4.1 or later.
See remediation →
61/100
Remediation priority · Elevated
Remotely reachable

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
An uncontrolled allocation of resources without limits or throttling in the e-mail handling in OTRS allows excessive allocation which may lead to the abortion of the webserver.This issue affects OTRS: * 8.0.X * 2023.X * 2024.X * 2025.X * 2026.X before 2026.4.X Please note that ((OTRS)) Community Edition 6.x, OTRS 7.x and products based on the ((OTRS)) Community Edition also very likely to be affected

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

Uncontrolled resource allocation in OTRS email handling allows attackers to cause excessive memory or CPU consumption by sending specially crafted emails, leading to webserver abortion (DoS). The vulnerability stems from missing resource limits or throttling in the email processing component.

MitigationUpgrade to OTRS 2026.4.X or later to receive the patch; alternatively, implement application-level resource limits and throttling on the email handling module as a compensating control.

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
OtrsApplication
Affected:<= 6.0.32>= 7.0.0, <= 8.0.37>= 2023.0.0, < 2026.4.1

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
Low
Privileges
Low
User interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

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

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 OTRS version
    Run 'perl -MOTRS::Version -e "print $OTRS::Version::Version"' or check the VERSION file in the OTRS root directory (typically /opt/otrs/VERSION or /opt/otrs8/VERSION)
    Affected if The installed version is <= 6.0.32, OR >= 7.0.0 and <= 8.0.37, OR >= 2023.0.0 and < 2026.4.1
  2. Verify PostMaster email module is active
    Check the OTRS system configuration at Admin > System Configuration > Core::PostMaster or inspect the PostMaster spool directory (var/spool/) for active email queue processing
    Affected if PostMaster is enabled and processing incoming emails from untrusted sources
  3. Examine email handling resource limits
    Navigate to Admin > System Configuration > PostMaster::PostMaster and inspect settings such as 'PostMasterMaxMessageSize', 'PostMasterMaxEmailsPerHour', and 'Ticket::Frontend::AgentTicketZoom###ArticlePreLimit' for configured thresholds
    Affected if No size limits, rate limits, or processing throttles are defined for incoming email handling
  4. Check system-level ulimits for OTRS service
    Run 'ulimit -a' as the OTRS system user or check systemd service file (systemctl cat otrs or systemctl cat otrs8) for LimitRSS, LimitAS, or LimitCPU settings
    Affected if No resource limits (memory, CPU, file descriptors) are imposed on the OTRS process
  5. Inspect email input parsing configuration
    Review Kernel/System/PostMaster.pm and Kernel/System/PostMaster/*.pm files for custom limits on email attachment size, header parsing, or body processing loops
    Affected if The email parsing logic lacks explicit bounds on memory allocation or iteration counts

A user is affected if their OTRS version falls within the vulnerable ranges AND the PostMaster email module is active with no resource constraints configured on email handling.

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
Upgrade available Upgrade to 2026.4.1 or later
Fixed in 2026.4.1
Interim mitigation

Upgrade to OTRS 2026.4.X or later to receive the patch; alternatively, implement application-level resource limits and throttling on the email handling module as a compensating control.

Recommended fix Moderate confidence

OTRS 2026.4.1 or later (or latest available 2026.x release)

  1. 1. Backup your OTRS database and configuration files before proceeding with any upgrade.
  2. 2. Review the OTRS upgrade documentation for your current version at https://doc.otrs.com/.
  3. 3. Upgrade OTRS 6.x to the latest 6.0.x version (6.0.33 or later if available), or preferably migrate to OTRS 2026.4.1 or later.
  4. 4. For OTRS 7.x installations, upgrade directly to OTRS 2026.4.1 or later.
  5. 5. For OTRS 2023.x, 2024.x, 2025.x, and 2026.x installations, upgrade to version 2026.4.1 or later.
  6. 6. After upgrade, verify email handling functionality works correctly.
  7. 7. Monitor server resource usage to confirm the resource consumption issue is resolved.
Caveat Review upgrade notes for potential breaking changes between your current version and 2026.4.x; custom scripts or modules may require updates

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

Fix this in Otrs Scoped from the published advisory
  • Consultation3.0 h
  • Implementation12.0 h
  • Testing6.0 h
  • Review / QA3.0 h
24.0 hours of engineering $4,200
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $6,720.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2026-48187 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2026-48187 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data