Security readout for executives and security teams
Plain-English summary
CVE-2021-46930 is a Linux kernel issue in the mtu3 USB gadget driver. The bug can trigger a use-after-free warning because a list_head was not initialized correctly. The sources do not provide CVSS, real-world impact, or active exploitation evidence, so business urgency depends on whether exposed systems use this driver and affected kernel versions.
Executive priority
Handle through normal kernel patch governance, with higher priority for appliances, embedded systems, or USB gadget deployments using mtu3. There is insufficient source evidence to justify emergency response solely for exploitation risk.
Technical view
The source describes an uninitialized list_head leading to a KASAN-reported use-after-free in __list_del_entry_valid during mtu3_req_complete, reached while stopping/unregistering the mtu3 USB gadget driver. The issue is marked resolved in Linux stable commits, but the bundle does not include a CVSS score, CWE, or detailed exploitability analysis.
Likely exposure
Exposure appears limited to Linux systems running affected kernels with the mtu3 USB gadget driver present or enabled. The provided version data identifies Linux kernel 5.2 and related stable lines through listed affected versions, but exact downstream distribution exposure requires vendor kernel mapping.
Exploitation context
The bundle shows no KEV listing and provides no cited evidence of active exploitation. The available evidence is a kernel bug report and stable fix references, not public exploitation details. Treat exploitability and attack preconditions as unconfirmed from the supplied sources.
Researcher notes
Useful follow-up is code and distribution mapping: determine which kernel branches include the stable commits and whether downstream kernels backported them. The source bundle does not define attacker control, privilege requirements, or reachable configurations.
Mitigation direction
- Map systems to Linux kernel versions and enabled mtu3 USB gadget support.
- Apply vendor or upstream Linux stable updates containing the referenced fixes.
- Check distribution advisories for backported kernel fixes before relying on version numbers alone.
- Prioritize embedded or USB gadget-capable Linux devices where mtu3 is enabled.
Validation and detection
- Confirm whether the running kernel includes or loads the mtu3 driver.
- Compare installed kernel packages against vendor advisories for CVE-2021-46930.
- Review kernel logs for KASAN or list corruption reports involving mtu3.
- Verify patched kernels include the referenced stable commits or downstream equivalents.
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.
CVE-2021-46930 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
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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
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/585e2b244dda7ea733274e4b8fa27853d625d3bfCVE reference, Linux
- https://git.kernel.org/stable/c/3b6efe0b7ba03cc2acf0694b46d6ff33c5b4c295CVE reference, Linux
- https://git.kernel.org/stable/c/249ddfbe00570d6dc76208e88017937d4d374c79CVE reference, Linux
- https://git.kernel.org/stable/c/8c313e3bfd9adae8d5c4ba1cc696dcbc86fbf9bfCVE 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.