Security readout for executives and security teams
Plain-English summary
This vulnerability affects Bitdefender GravityZone Endpoint Security Tools for Windows. A local, low-privileged attacker could abuse link handling in the EPAG component to disrupt endpoint protection or system availability. It is not remotely exploitable based on the supplied CVSS vector, but it matters where attackers may already have local access.
Executive priority
Handle through normal vulnerability remediation with priority for high-value Windows endpoints. This is not presented as actively exploited or remotely reachable, but it can affect endpoint availability if an attacker already has local access.
Technical view
CVE-2021-3641 is a CWE-59 improper link resolution issue before file access in Bitdefender GravityZone EPAG. The supplied CVSS vector is local, low complexity, low privileges, no user interaction, with no confidentiality impact, low integrity impact, and high availability impact. Affected versions are GravityZone 7.1.2.33 and prior.
Likely exposure
Exposure is most likely on Windows endpoints running Bitdefender Endpoint Security Tools managed through GravityZone version 7.1.2.33 or earlier. Risk increases on shared workstations, developer machines, terminal servers, and any endpoint where untrusted local users or malware may obtain low-privileged access.
Exploitation context
The source bundle does not show CISA KEV listing or confirmed active exploitation. Exploitation requires local access with low privileges and does not require user interaction. Treat this as a post-compromise or insider-risk issue rather than an internet-facing emergency.
Researcher notes
Do not broaden scope beyond the supplied sources: EPAG in Bitdefender Endpoint Security Tools for Windows, GravityZone 7.1.2.33 and prior. The bundle does not provide exploit details, fixed version text, or observed exploitation evidence. Validation should focus on version inventory and vendor advisory alignment.
Mitigation direction
- Inventory Bitdefender GravityZone and Endpoint Security Tools versions on Windows endpoints.
- Upgrade affected installations according to Bitdefender’s advisory and current vendor guidance.
- Prioritize endpoints with shared users, elevated business criticality, or recent compromise indicators.
- Restrict local interactive access on systems where affected versions cannot be promptly updated.
- Monitor Bitdefender advisory channels for fixed-version and deployment guidance.
Validation and detection
- Confirm whether any Windows endpoint runs GravityZone or BEST version 7.1.2.33 or earlier.
- Verify updated endpoints report a non-affected version in management inventory.
- Review endpoint logs for unexplained Bitdefender service failures or availability disruptions.
- Check vulnerability management records for CVE-2021-3641 coverage and remediation status.
- Confirm the vulnerability is not treated as actively exploited unless new sourced evidence appears.
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-59: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. 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-2021-3641 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:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A: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.
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:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H1.84.2Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.1MediumVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://www.bitdefender.com/support/security-advisories/improper-link-resolution-before-file-access-in-bitdefender-gravityzone-va-9921CVE reference · x_refsource_MISC
- https://www.zerodayinitiative.com/advisories/ZDI-22-143/CVE 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 Link Resolution Before File Access ('Link Following')
Improper Link Resolution Before File Access ('Link Following') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.