CVE-2026-43503
Description
A flaw was found in the Linux kernel's networking (skbuff) component. When skb_try_coalesce() attaches paged fragments, it can lose the SKBFL_SHARED_FRAG marker. This can lead to the Encapsulating Security Payload (ESP) input decrypting data in place over page-cache backed fragments, potentially resulting in data corruption.
Security Bulletin
Statement
Impact is rated as Important because the privileged file-backed cache pages may be modified through a shared-page ownership bypass. Within Red Hat Enterprise Linux and Red Hat OpenShift Container Platform, this vulnerability was fixed at the same time as CVE-2026-46300.
Mitigation
See the security bulletin for a detailed mitigation procedure.
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7 | N/A | 7 |
| Attack Vector | Local | N/A | Local |
| Attack Complexity | High | N/A | High |
| Privileges Required | Low | N/A | Low |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | High | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
cve.org: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Other
Technical Impact: Other
Frequently Asked Questions
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