Security readout for executives and security teams
Plain-English summary
This vulnerability affects certain FV Flowplayer Video Player WordPress plugin versions. A crafted link could cause a visitor’s browser to run attacker-supplied script on the affected site. It requires user interaction, but could expose session data or modify page behavior in the victim’s browser context.
Executive priority
Treat as a medium-priority web risk. Patch or remove affected plugin instances during normal vulnerability remediation, with faster handling for public sites used by administrators, customers, or logged-in users.
Technical view
CVE-2021-39350 is reflected cross-site scripting in the player_id parameter of view/stats.php in FV Flowplayer Video Player versions 7.5.0.727 through 7.5.2.727. It is CWE-79 with CVSS 3.1 score 6.1, network exploitable, low complexity, no privileges required, and user interaction required.
Likely exposure
Exposure is limited to WordPress sites running FV Flowplayer Video Player in the listed affected version range. Internet-facing WordPress sites are the primary concern, especially where administrators or authenticated users may click attacker-controlled links.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation evidence. Practical exploitation depends on convincing a user to open a crafted URL to an affected site. Impact is browser-side confidentiality and integrity risk, not direct server takeover based on the cited data.
Researcher notes
Evidence identifies the vulnerable parameter and file, affected plugin range, CWE-79, CVSS vector, and a WordPress Trac changeset reference. The provided sources do not establish active exploitation, broad compromise, or a specific fixed version beyond the affected range.
Mitigation direction
- Inventory WordPress sites for FV Flowplayer Video Player and affected versions.
- Update only according to vendor or Wordfence guidance; confirm version is outside the affected range.
- Disable or remove the plugin where it is not business-required.
- Warn administrators against opening unsolicited links to affected WordPress sites.
Validation and detection
- Check installed plugin versions against 7.5.0.727 through 7.5.2.727.
- Review whether view/stats.php is present in deployed plugin files.
- Confirm remediation against vendor, Wordfence, or WordPress Trac guidance.
- Review web logs for unusual requests to view/stats.php with player_id parameters.
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-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. 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 lookupCVE-2021-39350 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
- Medium
- CVSS
- 6.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
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.
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:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N2.82.7Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.1MediumVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.wordfence.com/vulnerability-advisories/#CVE-2021-39350CVE reference · x_refsource_MISC
- https://plugins.trac.wordpress.org/changeset/2580834/fv-wordpress-flowplayer/trunk/view/stats.phpCVE reference · x_refsource_MISC
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.
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.