dbcve.org
OssimApplication · Alienvault

CVE-2016-7955

CRITICAL · 9.8 CVSS v3.0 Published 2017-03-15
Fix available
A fix is available. Upgrade to after 5.3 or later.
See remediation →
100/100
Remediation priority · Urgent
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
The logcheck function in session.inc in AlienVault OSSIM before 5.3.1, when an action has been created, and USM before 5.3.1 allows remote attackers to bypass authentication and consequently obtain sensitive information, modify the application, or execute arbitrary code as root via an "AV Report Scheduler" HTTP User-Agent header.

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

The logcheck function in session.inc in AlienVault OSSIM before 5.3.1 and USM before 5.3.1 contains an authentication bypass vulnerability. Remote attackers can bypass authentication by sending a specially crafted HTTP request with an 'AV Report Scheduler' User-Agent header, allowing them to execute arbitrary code with root privileges.

MitigationUpgrade to AlienVault OSSIM/USM version 5.3.1 or later to obtain the patched session management code. If immediate upgrading is not possible, implement network-level access controls to restrict administrative interfaces to trusted IP addresses only.

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
OssimApplication
Affected:<= 5.3
Unified Security ManagementApplication
Affected:<= 5.3

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
None
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/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 AlienVault version
    Access the AlienVault web UI and navigate to 'System > About' or use the command line: 'alienvault-api --version' or 'rpm -q alienvault-idm 2>/dev/null' to retrieve the installed OSSIM or USM version number
    Affected if The installed version is 5.3 or any version lower than 5.3.1 (for both OSSIM and USM)
  2. Verify web administrative interface is accessible
    Confirm that the AlienVault OSSIM/USM web interface (HTTPS on port 443) is reachable from network locations. Attempt to access the login page from an external or untrusted network
    Affected if The administrative web interface is exposed to untrusted networks, making it reachable for remote attackers
  3. Examine session.inc for vulnerable logcheck function
    Locate the session.inc file in the AlienVault installation directory (typically in /var/www/html/ossim/ or similar paths under /usr/share/ossim/), then inspect the logcheck function for authentication logic that relies solely on User-Agent matching without proper session validation
    Affected if The session.inc file contains a logcheck function that grants authentication based solely on the 'AV Report Scheduler' User-Agent header without validating session credentials
  4. Review HTTP access logs for exploitation attempts
    Check the Apache or Nginx access logs (typically in /var/log/apache2/ or /var/log/nginx/) for incoming requests with 'AV Report Scheduler' in the User-Agent header that successfully accessed protected endpoints without proper authentication

A system is affected if it runs AlienVault OSSIM or USM version 5.3 or earlier AND has its web administrative interface network-accessible, since the authentication bypass requires sending an HTTP request with the specific User-Agent header to the vulnerable session.inc logcheck function.

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 a release after 5.3
Interim mitigation

Upgrade to AlienVault OSSIM/USM version 5.3.1 or later to obtain the patched session management code. If immediate upgrading is not possible, implement network-level access controls to restrict administrative interfaces to trusted IP addresses only.

Recommended fix High confidence

AlienVault OSSIM/USM version 5.3.1 or later

  1. 1. Check current OSSIM/USM version using command: 'alienvault-api --version' or 'rpm -qa | grep alienvault'
  2. 2. Create a full backup of the OSSIM/USM database and configuration files before upgrading
  3. 3. Run system update check: 'alienvault-update --check'
  4. 4. Upgrade to version 5.3.1 or later using the AlienVault update mechanism: 'alienvault-update --upgrade'
  5. 5. After upgrade, verify the session.inc file has been updated by checking the file modification date and reviewing the logcheck function for the patched code
  6. 6. Confirm the new version is >= 5.3.1 using: 'alienvault-api --version'
  7. 7. Test authentication to ensure normal login works correctly after the patch
Caveat Review AlienVault 5.3.1 release notes for any configuration changes or migration requirements before upgrading production systems

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

Fix this in Ossim Scoped from the published advisory
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2016-7955 — 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-2016-7955 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