Security readout for executives and security teams
Plain-English summary
A Linux kernel flaw in the s3c24xx I2C driver allows an invalid SMBus message length to be processed without first checking its permitted range. Exploitation is assessed as local and requires low privileges. Successful exploitation could seriously affect confidentiality, integrity, and availability, although the supplied sources do not describe the precise failure mechanism.
Executive priority
Use an expedited patch cycle for embedded or Linux systems that actively use this driver, especially where untrusted users have local access. First determine driver usage because the issue is hardware and driver specific. Treat the raw version list cautiously and obtain exact fixed-package confirmation from the operating-system or device vendor.
Technical view
The first SMBus message byte specifies block size and must be between zero and I2C_SMBUS_BLOCK_MAX. The s3c24xx driver used that value before validating it. Linux resolved the issue by adding the missing bounds check, following equivalent logic previously added to the Tegra I2C driver. CVSS 3.1 scores it 7.8: local, low-complexity, low-privilege, no-user-interaction.
Likely exposure
Exposure is concentrated in Linux systems that run an affected kernel and actively use the s3c24xx I2C driver for SMBus operations. Systems without that driver or relevant hardware are unlikely to be exposed. The supplied affected-version data is ambiguous and should not replace distribution or vendor package guidance.
Exploitation context
The bundle marks this CVE as absent from KEV, and no supplied source reports active exploitation or a public exploit. The CVSS vector indicates a local attacker with low privileges, not a remote unauthenticated attacker. Absence of cited exploitation evidence does not prove exploitation has never occurred.
Researcher notes
The validated range is 0 through I2C_SMBUS_BLOCK_MAX. The fix checks the SMBus size byte before processing, mirroring an earlier Tegra-driver correction. The bundle supplies no CWE, crash trace, proof of concept, or detailed memory-safety consequence, so a specific corruption primitive or privilege-escalation path cannot be confirmed from these sources.
Mitigation direction
- Upgrade to a vendor kernel explicitly documented as containing the applicable CVE-2026-31627 fix.
- Consult distribution or device-vendor guidance for exact fixed package and firmware versions.
- Prioritize systems actively using the s3c24xx I2C driver and permitting untrusted local access.
- Reduce untrusted local account access until affected systems are confirmed patched.
Validation and detection
- Inventory running kernel and vendor package versions on systems using relevant Samsung-platform hardware.
- Confirm whether the s3c24xx I2C driver is present and active.
- Map each kernel package to vendor guidance or the applicable linked Linux stable fix.
- After upgrading, verify the fixed kernel is running and normal I2C or SMBus operations still succeed.
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-2026-31627 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.
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.
Source materials
- CVE List V5 sourceCVE List V5
- https://git.kernel.org/stable/c/fd1650da24ed54c716aa9b69e9bbd8a662e492daCVE reference, Linux
- https://git.kernel.org/stable/c/8f756a5964396da0fc9e0db33253a5b85dbbcbb6CVE reference, Linux
- https://git.kernel.org/stable/c/2d262da4bca6fab96e2e709feb95b31b0a9a03a7CVE reference, Linux
- https://git.kernel.org/stable/c/fa00738ab30b07db1a43b9c85fc56b8cc3b7d197CVE reference, Linux
- https://git.kernel.org/stable/c/d87d5620125a03b1eadbd5df39748215d3db7ddbCVE reference, Linux
- https://git.kernel.org/stable/c/377fae22a137b6b89f3f32399a58c52cf2325416CVE reference, Linux
- https://git.kernel.org/stable/c/71b3c316b22c555d2769126a92b1244b15a9750dCVE reference, Linux
- https://git.kernel.org/stable/c/aaaaec39ddbcd06770dca7f1adebc3b1242ebe7bCVE reference, Linux
- https://git.kernel.org/stable/c/c0128c7157d639a931353ea344fb44aad6d6e17aCVE 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.