Skip to main content

Linux Kernel CVE-2026-68385

| EUVDEUVD-2026-55571 CRITICAL
2026-08-10 Linux GHSA-p69g-gmqr-g4rm
Critical
Disputed · 9.8 Vendor: Linux
Share

Severity by source

Sources disagree (Medium–Critical)
Vendor (Linux) PRIMARY
9.8 CRITICAL
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
vuln.today AI
3.6 LOW

Local s390-only path gated on absent vector hardware (AV:L/AC:H); needs local execution (PR:L); worst case is limited address-zero info leak and checksum corruption (C:L/I:L), no availability impact.

3.1 AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:N
4.0 AV:L/AC:H/AT:P/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
SUSE
5.5 MEDIUM
AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Red Hat
5.5 MEDIUM
qualitative

vuln.today treats the vendor’s rating as authoritative. A higher third-party CVSS (e.g. CISA-ADP) is shown for transparency but does not drive the headline severity.

CVSS VectorVendor: Linux

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

Lifecycle Timeline

5
Analysis Generated
Aug 14, 2026 - 02:53 vuln.today
CVSS changed
Aug 13, 2026 - 23:37 NVD
9.8 (CRITICAL)
Patch available
Aug 10, 2026 - 14:18 EUVD
CVE Published
Aug 10, 2026 - 12:04 cve.org
CRITICAL 9.8
CVE Published
Aug 10, 2026 - 12:04 cve.org
UNKNOWN (no severity yet)

DescriptionCVE.org

In the Linux kernel, the following vulnerability has been resolved:

s390/checksum: Fix csum_partial() without vector facility

Currently csum_partial() calls csum_copy() with copy=false and dst=NULL. On machines without the vector facility, csum_copy() falls back to cksm(dst, ...), causing the checksum to be calculated from address zero instead of the source buffer.

The VX implementation already checksums data loaded from src. Make the fallback do the same by passing src to cksm().

AnalysisAI

Incorrect checksum computation in the Linux kernel's s390 (IBM Z mainframe) architecture code causes csum_partial() to read from memory address zero instead of the intended source buffer on machines lacking the vector (VX) facility. Affects s390 systems running the buggy kernel builds; the practical effect is corrupted checksums and potential leakage of kernel memory contents near address zero into computed checksums. Rated CVSS 9.8 by automated scoring, but this is a local architecture-specific correctness bug with no public exploit identified at time of analysis and a low EPSS (0.18%, 7th percentile).

Technical ContextAI

The issue lives in the s390 checksum implementation (arch/s390 checksum path) of the Linux kernel. csum_partial() invokes csum_copy() with copy=false and dst=NULL. On CPUs with the vector facility, the VX implementation correctly checksums data loaded from the src pointer. On CPUs without the vector facility, csum_copy() falls back to the hardware cksm instruction using dst (which is NULL/address zero) rather than src, so the checksum is derived from address zero rather than the real source buffer. The CWE is not assigned (N/A), but the root cause is an incorrect pointer/argument being passed to a fallback code path, producing use of an unintended memory address - a logic/pointer-handling defect rather than a classic memory-safety overflow.

RemediationAI

Vendor-released patch: upgrade to a fixed stable kernel - 6.12.101, 6.18.42, 7.1.6, or 7.2-rc4 (or later on the respective branch) - which passes src to cksm() in the fallback so it checksums the correct buffer. The upstream fix is available as stable commits (https://git.kernel.org/stable/c/5fc0a2a6eeb99cac991242bb48796c7749ce3261, .../1d9a2f01b3c4e5c88e06b2db4b5460c2ec884722, .../898bb2814f38399108bdd2113f38d97383a7036a, .../4bb06b60d982355e22647b3d12d6619419f8c1fa); apply the one matching your stable series. As a non-patch note, the defect only manifests on s390 hardware lacking the vector facility, so environments running s390 guests/hosts on VX-capable CPUs are not exposed and can prioritize accordingly; there is no meaningful runtime workaround short of applying the fixed kernel.

Vendor StatusVendor

SUSE

Severity: Moderate
Product Status
SUSE Linux Enterprise Desktop 15 SP7 Not-Affected
SUSE Linux Enterprise Desktop 15 SP7 Not-Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 Not-Affected
SUSE Linux Enterprise High Availability Extension 15 SP7 Not-Affected
SUSE Linux Enterprise High Availability Extension 16.0 Affected

Share

CVE-2026-68385 vulnerability details – vuln.today

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy