Security readout for executives and security teams
Plain-English summary
CVE-2025-21990 is a Linux kernel AMDGPU driver flaw that can crash affected systems when code dereferences a missing graphics buffer backing store. It is a local availability issue, not a data theft or remote compromise issue based on the provided sources.
Executive priority
Handle through normal-to-priority kernel patching, with faster action for shared Linux systems using AMD GPUs. This does not currently justify emergency response absent exploitation evidence, but it can affect system availability.
Technical view
The issue is CWE-476 in drm/amdgpu. PRT buffer objects may have a NULL tbo.resource, and the GFX12 PTE flag path dereferenced it without checking. The fix adds a NULL check before use. CVSS is 5.5: local, low complexity, low privilege, no user interaction, availability high.
Likely exposure
Exposure is most relevant to Linux systems running affected kernel builds with the AMDGPU driver path present, especially where low-privileged local users can access graphics functionality. The supplied affected-version data names Linux 6.11, 6.12.20, 6.13.8, and 6.14, but package-level distribution status is not provided.
Exploitation context
The CVE is not listed as KEV, and the bundle provides no evidence of active exploitation. The CVSS vector indicates local access with low privileges is required. The expected impact is denial of service through kernel crash or instability, not confidentiality or integrity loss.
Researcher notes
The source evidence supports a narrow NULL pointer dereference in AMDGPU GFX12 PTE flag handling for PRT BOs lacking backing store. Avoid expanding scope beyond Linux kernel AMDGPU. Distribution backport status and exact package fixed versions must be verified separately.
Mitigation direction
- Update to a vendor or distribution kernel containing the referenced stable fixes.
- Track the CVE in Linux distribution security advisories for package-specific fixed versions.
- Prioritize systems using AMDGPU on shared or untrusted multi-user Linux hosts.
- Limit untrusted local access to affected systems where patching is delayed.
Validation and detection
- Inventory Linux kernel versions and identify hosts using AMDGPU graphics support.
- Check kernel package changelogs for CVE-2025-21990 or the referenced stable commit IDs.
- Confirm whether distribution advisories mark your installed kernel as fixed or affected.
- Review crash reports for AMDGPU NULL pointer dereference symptoms, if instability occurred.
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-476: 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-2025-21990 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/72235808eabea93055b459a63443bd9cd6b08aa4CVE reference, Linux
- https://git.kernel.org/stable/c/af23e39b9e9280b1f6299b6f2fa090a1694240adCVE reference, Linux
- https://git.kernel.org/stable/c/6cc30748e17ea2a64051ceaf83a8372484e597f1CVE 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.
NULL Pointer Dereference
NULL Pointer Dereference represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.