Security readout for executives and security teams
Plain-English summary
A highly privileged Piwik Superuser could turn the plugin upload feature into server-side PHP code execution in versions before 3.0.3. This is serious where old Piwik/Matomo instances remain exposed, but it is not a drive-by bug: attacker access must already include Superuser privileges.
Executive priority
Treat as urgent for any legacy Piwik instance with administrative exposure. Prioritize upgrade, Superuser account review, and plugin-upload configuration checks before broader low-risk backlog work.
Technical view
The issue is an authenticated RCE through custom plugin ZIP upload and activation. Vulnerable Piwik versions before 3.0.3 allowed a Superuser to upload plugin code that could execute as PHP on the host. Version 3.0.3 changed behavior so plugin upload is disabled by default unless enabled in configuration.
Likely exposure
Exposure is most likely in legacy Piwik deployments below 3.0.3, especially internet-facing analytics portals where Superuser accounts are numerous, shared, weakly protected, or previously compromised.
Exploitation context
The source bundle cites a public exploit reference and third-party writeups. However, KEV is false and no provided source confirms active exploitation. Practical abuse requires authenticated Superuser access first.
Researcher notes
The affected-version metadata in the bundle is sparse, but the description and references identify Piwik before 3.0.3. Do not treat this as unauthenticated RCE; privilege requirement is high, but post-compromise impact is full server code execution.
Mitigation direction
- Upgrade Piwik/Matomo to 3.0.3 or later per vendor guidance.
- Keep plugin upload disabled unless explicitly required.
- Review configuration for settings that re-enable plugin upload.
- Restrict and audit Superuser accounts.
- Harden Superuser authentication with strong credentials and MFA where available.
- Check current vendor guidance for supported upgrade paths.
Validation and detection
- Inventory all Piwik/Matomo instances and record exact versions.
- Confirm whether plugin upload is enabled in configuration.
- Review Superuser account list for stale or shared accounts.
- Check audit logs for unexpected plugin uploads or activations.
- Verify web server files for unapproved custom plugins.
- Confirm upgraded instances keep plugin upload disabled by default.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-306: Credential and account abuse lookup
Authentication and credential weaknesses can make valid-account abuse and credential telemetry useful review starting points. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCWE-434: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2025-34104 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.4 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
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.
SSVC decision data
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H——VulnCheckVulnerability scoring details
Base CVSS 4.0 score
9.4CriticalVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- https://matomo.org/changelog/piwik-3-0-3/CVE reference, VulnCheck · vendor-advisory
- https://matomo.org/faq/plugins/faq_21/CVE reference, VulnCheck · product
- https://firefart.at/post/turning_piwik_superuser_creds_into_rce/CVE reference, VulnCheck · third-party-advisory
- https://raw.githubusercontent.com/rapid7/metasploit-framework/master/modules/exploits/unix/webapp/piwik_superuser_plugin_upload.rbCVE reference, VulnCheck · exploit
- https://www.vulncheck.com/advisories/piwik-authenticated-rce-via-custom-plugin-uploadCVE reference, VulnCheck · third-party-advisory
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Missing Authentication for Critical Function
Missing Authentication for Critical Function represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.
Unrestricted Upload of File with Dangerous Type
Unrestricted Upload of File with Dangerous Type represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.