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CVE Record

CVE-2019-16993: In phpBB before 3.1.7-PL1, includes/acp/acp_bbcodes.php has improper verification of a CSRF token on the BB...

In phpBB before 3.1.7-PL1, includes/acp/acp_bbcodes.php has improper verification of a CSRF token on the BBCode page in the Administration Control Panel. An actual CSRF attack is possible if an attacker also manages to retrieve the session id of a reauthenticated administrator prior to targeting them.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

This flaw affects older phpBB forums before 3.1.7-PL1. An attacker could abuse an administrator’s browser to make BBCode administration changes, but the public description says this requires the attacker to first obtain a reauthenticated administrator session ID. That prerequisite lowers urgency, but exposed legacy forums should still be updated.

Executive priority

Treat this as a legacy-platform cleanup item unless phpBB administration is internet-exposed or administrators are high-value targets. Prioritize patching any pre-3.1.7-PL1 forum because the vulnerable code affects administrator actions.

Technical view

The issue is improper CSRF token verification in includes/acp/acp_bbcodes.php on the Administration Control Panel BBCode page. The vulnerable range is phpBB before 3.1.7-PL1. Public sources do not provide CVSS, CWE, detailed impact scope, or confirmed exploitation.

Likely exposure

Exposure is likely limited to organizations still running phpBB versions before 3.1.7-PL1, including older packaged phpbb3 deployments. The vulnerable surface is administrative BBCode management, not normal anonymous forum browsing alone.

Exploitation context

The CVE states a real CSRF attack is possible only if the attacker also retrieves the session ID of a reauthenticated administrator before targeting them. The bundle shows KEV is false and provides no cited evidence of active exploitation.

Researcher notes

The public record is sparse: no CVSS, CWE, or active exploitation evidence is included. The key condition is the additional need for a reauthenticated administrator session ID. Analysis should focus on legacy version discovery, ACP exposure, and whether vendor or Debian fixes are installed.

Mitigation direction

  • Upgrade phpBB to 3.1.7-PL1 or later.
  • Apply supported distribution security updates for packaged phpbb3 deployments.
  • Review phpBB vendor guidance and changelogs for upgrade sequencing.
  • Restrict and monitor Administration Control Panel access.
  • Invalidate administrator sessions after patching legacy instances.

Validation and detection

  • Inventory phpBB installations and confirm their exact versions.
  • Check Debian phpbb3 package status where Debian packages are used.
  • Verify includes/acp/acp_bbcodes.php includes the vendor CSRF fix.
  • Review ACP BBCode change history for unauthorized modifications.
  • Confirm administrator session handling after the update.
Prepared
Confidence
medium
Sources
7

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

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ATT&CK lookup starting points

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description · low confidence lookup

Credential and access behavior lookup

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cve · low confidence lookup

CVE-2019-16993 mapping review

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
6Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.