Security readout for executives and security teams
Plain-English summary
CVE-2025-21843 is a Linux kernel panthor DRM driver bug where uninitialized data could be returned to a user object during a device query. The CVSS impact emphasizes local, low-privilege availability risk. Public sources do not show active exploitation or a remote attack path.
Executive priority
Treat this as a moderate-priority kernel maintenance issue. It is not supported as remotely exploitable or actively exploited, but local kernel bugs can matter on shared servers, developer workstations, and systems running untrusted workloads.
Technical view
In panthor_ioctl_dev_query(), priorities_info was not initialized before PANTHOR_UOBJ_SET() copied it to a user object. The kernel fix initializes the structure with memset. The CVE is mapped to CWE-908 and scored CVSS 5.5 with local attack vector, low complexity, low privileges, no user interaction, and high availability impact.
Likely exposure
Exposure is most likely on Linux systems running affected 6.13 or 6.14 kernel lines with the panthor DRM driver present. Downstream distribution risk depends on whether the vendor kernel includes the vulnerable code or a backported stable fix.
Exploitation context
The CVE is not listed as KEV, and the provided sources do not cite active exploitation. The CVSS vector requires local access and low privileges, with no user interaction. No public exploit details are provided in the source bundle.
Researcher notes
Evidence is limited to the CVE record and kernel stable commits. The root cause is uninitialized priorities_info copied to userspace during a panthor device query. Avoid assuming broader product impact beyond Linux kernels and panthor code paths identified by the sources.
Mitigation direction
- Apply Linux kernel stable updates containing the referenced fixes.
- Check distribution advisories for backported kernel packages covering CVE-2025-21843.
- Prioritize affected multi-user systems where untrusted local users can run code.
- If patch timing is unclear, follow vendor guidance for panthor DRM exposure reduction.
Validation and detection
- Inventory Linux kernel versions and identify systems on affected 6.13 or 6.14 lines.
- Confirm whether vendor kernel packages include the referenced stable commits.
- Check whether the panthor DRM driver is present or enabled on exposed systems.
- Track CVE-2025-21843 status in distribution security advisories and patch management records.
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-908: 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-2025-21843 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/64b95bbc08bacf3e4b05c8604e6a4fec43bb712aCVE reference, Linux
- https://git.kernel.org/stable/c/3b32b7f638fe61e9d29290960172f4e360e38233CVE 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.
Use of Uninitialized Resource
Use of Uninitialized Resource represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.