Security readout for executives and security teams
Plain-English summary
A local user with existing access may submit oversized vmwgfx graphics command header data. Missing size validation could overflow kernel offset calculations and access memory outside intended bounds, threatening confidentiality, integrity, and availability. Severity is high, but the supplied evidence does not show remote or active exploitation.
Executive priority
Treat this as a high-priority kernel remediation for exposed multi-user Linux systems, especially those permitting untrusted local sessions. It is not internet-remote based on the supplied vector, and no active exploitation is cited. Schedule prompt vendor-supported updates after confirming vmwgfx exposure.
Technical view
The drm/vmwgfx command parser accepted a userspace-controlled command header size without checking it against SVGA_CMD_MAX_DATASIZE. The value feeds buffer-offset arithmetic, creating potential integer overflow and out-of-bounds access. CVSS 3.1 is 7.8: local, low complexity, low privileges, no user interaction, unchanged scope, and high confidentiality, integrity, and availability impacts.
Likely exposure
Exposure is most likely on Linux systems where vmwgfx is present and reachable by low-privileged local users. The bundle identifies releases across multiple stable lines, from 4.3 through 6.18, but lacks sufficient packaging detail to determine every distribution's status. Vendor backports must be checked.
Exploitation context
The CVSS vector requires local access and low privileges; user interaction is unnecessary. The bundle marks KEV false and provides no evidence of exploitation in the wild or public exploit availability. KEV absence alone does not prove exploitation is impossible.
Researcher notes
Eight stable-kernel commits are linked, consistent with fixes across maintained branches. The supplied data identifies no CWE, proof of concept, or confirmed exploit. Version entries are too compressed to establish exact distribution boundaries; analyze vendor backports and the relevant stable commit for each kernel line.
Mitigation direction
- Apply a kernel update containing the applicable referenced stable fix or an authorized vendor backport.
- Consult the Linux distribution or appliance vendor for package-specific fixed versions and reboot requirements.
- Prioritize multi-user systems where untrusted local users can reach vmwgfx functionality.
- If updating is delayed, restrict untrusted local access and follow vendor-approved temporary mitigations.
Validation and detection
- Inventory kernel versions and determine whether vmwgfx is installed, loaded, or otherwise reachable.
- Map each kernel package to its vendor advisory and applicable stable-fix commit.
- Confirm the running kernel contains the header-size validation against SVGA_CMD_MAX_DATASIZE.
- After updating, verify the intended kernel is running and repeat exposure 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.
CVE-2025-40277 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
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:H/A:H1.85.9LinuxVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/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/e58559845021c3bad5e094219378b869157fad53CVE reference, Linux
- https://git.kernel.org/stable/c/54d458b244893e47bda52ec3943fdfbc8d7d068bCVE reference, Linux
- https://git.kernel.org/stable/c/709e5c088f9c99a5cf2c1d1c6ce58f2cca7ab173CVE reference, Linux
- https://git.kernel.org/stable/c/a3abb54c27b2c393c44362399777ad2f6e1ff17eCVE reference, Linux
- https://git.kernel.org/stable/c/b5df9e06eed3df6a4f5c6f8453013b0cabb927b4CVE reference, Linux
- https://git.kernel.org/stable/c/5aea2cde03d4247cdcf53f9ab7d0747c9dca1cfcCVE reference, Linux
- https://git.kernel.org/stable/c/f3f3a8eb3f0ba799fae057091d8c67cca12d6fa0CVE reference, Linux
- https://git.kernel.org/stable/c/32b415a9dc2c212e809b7ebc2b14bc3fbda2b9afCVE 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.