CVE-2026-89846
Description
A flaw was found in the Linux kernel's scsi: qla2xxx driver. A remote attacker, by sending a specially crafted Fibre Channel Protocol (FCP) response, could cause an integer underflow. This underflow leads to an out-of-bounds read when handling sense data, potentially disclosing sensitive memory information from the kernel's heap.
Mitigation
If QLogic Fibre Channel HBAs are not in use, the 'qla2xxx' kernel module can be blacklisted to prevent it from loading. This can be achieved by creating a modprobe configuration file.
To blacklist the module:
1. Create a file named `/etc/modprobe.d/blacklist-qla2xxx.conf` with the following content:
`blacklist qla2xxx`
2. Regenerate the initramfs to ensure the blacklist is applied during boot:
`sudo dracut -f -v` (for RHEL 7/8/9)
`sudo mkinitcpio -P` (for Arch-based systems, if applicable)
3. Reboot the system for the changes to take effect.
Warning: Blacklisting this module will disable functionality for QLogic Fibre Channel HBAs. Ensure that this hardware is not required before applying this mitigation. A system reboot is required for the changes to take effect.
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 | 7.1 | N/A | 9.1 |
| Attack Vector | Local | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | Low | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | High | N/A | High |
| Integrity Impact | None | N/A | None |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.
Confidentiality
Technical Impact: Bypass Protection Mechanism
Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.
Other
Technical Impact: Varies by Context
The read operation could produce other undefined or unexpected results.
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