Security readout for executives and security teams
Plain-English summary
This is a Linux kernel memory leak in the staging media zoran driver. A local, low-privileged user could affect availability, but the sources do not show data theft, data modification, or remote exploitation. Business risk is mainly denial-of-service on systems using the affected driver.
Executive priority
Treat as moderate priority. It is local and availability-focused, so it is below remote code execution urgency, but should be remediated through normal kernel patch cycles, especially on systems with local user access or media-driver exposure.
Technical view
CVE-2021-47644 is a CWE-401 memory leak involving zr->video_dev handling in the Linux kernel zoran media driver. The fix restructures videodev allocation around zr36057_init(). CVSS 3.1 is 5.5: local attack vector, low complexity, low privileges, no user interaction, availability impact only.
Likely exposure
Exposure is most likely on Linux systems running affected kernel versions with the staging media zoran driver present or enabled. The bundle provides Linux kernel version and commit references but no CPEs or distribution-specific package names.
Exploitation context
The source bundle does not report active exploitation, and KEV is false. The CVSS vector requires local access with low privileges. No cited source provides exploit details, public weaponization status, or evidence of remote attack paths.
Researcher notes
Affected data includes Linux version ranges and commit identifiers, but no CPEs. Validate exposure through kernel configuration, module presence, and distro backport status. Do not assume every Linux host is affected without confirming zoran driver availability.
Mitigation direction
- Apply kernel updates containing the referenced stable fixes.
- Check Linux distribution advisories for backported fixed kernel packages.
- Prioritize systems where the zoran media driver is present or enabled.
- If patching is delayed, follow vendor guidance for reducing driver exposure.
Validation and detection
- Inventory Linux kernel versions across servers, workstations, and appliances.
- Confirm whether the zoran staging media driver is built, loaded, or packaged.
- Map installed distro kernels to vendor advisories or fixed stable commits.
- Verify patched systems no longer match affected kernel ranges.
Public sources used
- CVE Program
- CVE List V5
- Linux stable commit 8dce4b265a5357731058f69645840dabc718c687
- Linux stable commit bd01629315ffd5b63da91d0bd529a77d30e55028
- Linux stable commit ff3357bffd9fb78f59762d8955afc7382a279079
- Linux stable commit c1ba65100a359fe28cfe37e09e10c99f247cbf1e
- Linux stable commit 1e501ec38796f43e995731d1bcd4173cb1ccfce0
- Linux stable commit 82e3a496eb56da0b9f29fdc5b63cedb3289e91de
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-401: 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-2021-47644 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
- 5.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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.
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:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H1.83.6CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A: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://git.kernel.org/stable/c/8dce4b265a5357731058f69645840dabc718c687CVE reference, Linux
- https://git.kernel.org/stable/c/bd01629315ffd5b63da91d0bd529a77d30e55028CVE reference, Linux
- https://git.kernel.org/stable/c/ff3357bffd9fb78f59762d8955afc7382a279079CVE reference, Linux
- https://git.kernel.org/stable/c/c1ba65100a359fe28cfe37e09e10c99f247cbf1eCVE reference, Linux
- https://git.kernel.org/stable/c/1e501ec38796f43e995731d1bcd4173cb1ccfce0CVE reference, Linux
- https://git.kernel.org/stable/c/82e3a496eb56da0b9f29fdc5b63cedb3289e91deCVE reference, Linux
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 Release of Memory after Effective Lifetime
Missing Release of Memory after Effective Lifetime represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.