CVE-2026-99153
Description
A flaw was found in the Linux kernel's SCSI subsystem within the libiscsi module. A malicious or compromised iSCSI storage target can trigger a denial of service (DoS) or data integrity issues by sending a crafted Reject Protocol Data Unit (PDU) containing an unvalidated Initiator Task Tag (ITT). Because the kernel fails to verify that the reflected task identifier corresponds to a valid in-flight request, it may attempt to process an uninitialized or freed task. This improper handling leads to a null-pointer dereference and a kernel crash, or causes read operations to complete without receiving actual data.
Statement
This vulnerability is rated as Important severity because an untrusted or compromised storage target can remotely induce a host kernel panic or corrupt data over the network without requiring prior local credentials. Red Hat Enterprise Linux systems are only vulnerable if configured as an iSCSI initiator and actively connected to a malicious or rogue target node. Because iSCSI initiator connectivity is not enabled or established by default on standard installations, exposure is limited to hosts utilizing networked iSCSI storage.
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).
The following CVSS metrics and score provided are preliminary and subject to review.
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 7.5 | N/A | 9.8 |
| Attack Vector | Network | N/A | Network |
| Attack Complexity | Low | N/A | Low |
| Privileges Required | None | N/A | None |
| User Interaction | None | N/A | None |
| Scope | Unchanged | N/A | Unchanged |
| Confidentiality | None | N/A | High |
| Integrity Impact | None | N/A | High |
| Availability Impact | High | N/A | High |
Vector
Red Hat: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
cve.org: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Understanding the Weakness (CWE)
Availability
Technical Impact: DoS: Crash, Exit, or Restart
NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.
Integrity,Confidentiality
Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory
In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.
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