Security readout for executives and security teams
Plain-English summary
A Linux kernel USB networking driver can read past a fixed-size structure while processing ipheth data. This could expose kernel memory or crash the system. The issue is local, not described as remotely exploitable in the supplied sources.
Executive priority
Treat as high priority for Linux fleets with local-user exposure or USB access. It is less urgent than internet-facing remote code execution, but kernel memory exposure and crash potential justify timely patching.
Technical view
CVE-2025-21741 is a CWE-125 out-of-bounds read in Linux kernel usbnet/ipheth DPE handling. The fix limits processed DPE entries to what fits in the fixed-size NDP16 header. CVSS 3.1 is 7.1 with local attack vector, low privileges, no user interaction, high confidentiality and availability impact.
Likely exposure
Systems running affected Linux kernel versions with the ipheth USB networking driver present or loadable are the relevant exposure. The source bundle does not identify remote network exposure or affected distributions.
Exploitation context
The bundle marks KEV as false and provides no cited evidence of active exploitation. The CVSS vector indicates a local, low-privilege attack path, but no exploit method or weaponized status is supplied.
Researcher notes
Evidence is limited to the CVE record and kernel stable commits. The key behavior is bounds enforcement for DPE processing against the NDP16 header size. No public exploit status, distro-specific package matrix, or runtime detection guidance is provided.
Mitigation direction
- Apply Linux kernel updates containing the referenced stable fixes.
- Prioritize systems where untrusted local users or USB device access are possible.
- Check distribution advisories for exact fixed package versions.
- Restrict unnecessary USB networking driver exposure where operationally feasible.
Validation and detection
- Inventory Linux kernel versions across endpoints and servers.
- Check whether ipheth is present, loadable, or used for USB tethering.
- Map installed kernels against vendor fixed versions and advisories.
- Confirm patch deployment with post-update kernel version checks.
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-125: 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-2025-21741 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
- High
- CVSS
- 7.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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:H/I:N/A:H1.85.2CISA-ADPVulnerability scoring details
Base CVSS 3.1 score
7.1HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/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/22475242ddb70e35c9148234be9a3aa9fb8efff9CVE reference, Linux
- https://git.kernel.org/stable/c/5835bf66c50ac2b85ed28b282c2456c3516ef0a6CVE reference, Linux
- https://git.kernel.org/stable/c/971b8c572559e52d32a2b82f2d9e0685439a0117CVE reference, Linux
- https://git.kernel.org/stable/c/ee591f2b281721171896117f9946fced31441418CVE 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.
Out-of-bounds Read
Out-of-bounds Read represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.