CVE-2022-50543
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Description
A double-free vulnerability was found in the Linux kernel RDMA RXE (soft-RoCE) driver's memory region handling. A local user with access to RDMA userspace verbs can register a memory region with parameters that cause initialization to fail, triggering error handling code that frees the mr->map structure twice, which leads to memory corruption and can result in denial of service via kernel crash or potentially privilege escalation through heap manipulation.
Statement
The issue arises because of incorrect error handling in the memory region registration path. When rxe_reg_user_mr() calls rxe_mr_init_user() and initialization fails, the error path frees the mr->map structure. However, the cleanup then calls rxe_mr_cleanup() through __rxe_cleanup(), which attempts to free mr->map again, resulting in a double-free. This vulnerability was introduced when a previous fix for duplicate mapping tables was reverted, inadvertently reintroducing the double-free condition. Under normal circumstances, a local user with permissions to use RDMA verbs (typically requiring membership in the rdma group or CAP_IPC_LOCK capability) can trigger this by registering user memory regions with specific parameters that cause initialization failure. Double-free vulnerabilities are well-known memory corruption primitives; while direct exploitation for privilege escalation requires understanding kernel heap layout, they provide attackers with a foundation for more sophisticated attacks beyond simple denial of service.
Mitigation
To mitigate this issue, prevent the rdma_rxe module from loading. See https://access.redhat.com/solutions/41278 for instructions on blacklisting kernel modules.
Additional Information
- This content is not included.Bugzilla 2402222: kernel: RDMA/rxe: Fix mr->map double free
- Content from cwe.mitre.org is not included.CWE-1341: Multiple Releases of Same Resource or Handle
- FAQ: Frequently asked questions about CVE-2022-50543
- Offline Security Data data is available for integration with other systems. See Offline Security Data API to get started.
External References
Content from www.cve.org is not included.https://www.cve.org/CVERecord?id=CVE-2022-50543
Content from nvd.nist.gov is not included.https://nvd.nist.gov/vuln/detail/CVE-2022-50543
Affected Packages and Issued Red Hat Security Errata
| Products / Services | Components | State | Errata |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | kernel | Not affected | |
| Red Hat Enterprise Linux 6 | kernel | Not affected | |
| Red Hat Enterprise Linux 7 | kernel | Not affected | |
| Red Hat Enterprise Linux 7 | kernel-rt | Not affected | |
| Red Hat Enterprise Linux 8 | kernel | Fixed | RHSA-2023:2951 |
| Red Hat Enterprise Linux 8 | kernel-rt | Fixed | RHSA-2025:22800 |
| Red Hat Enterprise Linux 8 | kernel | Fixed | RHSA-2025:22801 |
| Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | kernel | Fixed | RHSA-2026:0536 |
| Red Hat Enterprise Linux 8.6 Telecommunications Update Service | kernel | Fixed | RHSA-2026:0536 |
| Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions | kernel | Fixed | RHSA-2026:0536 |
| Red Hat Enterprise Linux 8.8 Telecommunications Update Service | kernel | Fixed | RHSA-2026:0532 |
| Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | kernel | Fixed | RHSA-2026:0532 |
| Red Hat Enterprise Linux 9 | kernel-rt | Affected | |
| Red Hat Enterprise Linux 9 | kernel | Fixed | RHSA-2023:6583 |
Common Vulnerability Scoring System (CVSS) Score Details
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 Authorities (CNA) source for its products and services (see Red Hat classifications ).
| CVSS v3 Score Breakdown | Red Hat | NVD |
|---|---|---|
| CVSS v3 Base Score | 7.8 | 7.8 |
| Attack Vector | Local | Local |
| Attack Complexity | Low | Low |
| Privileges Required | Low | Low |
| User Interaction | None | None |
| Scope | Unchanged | Unchanged |
| Confidentiality Impact | High | High |
| Integrity Impact | High | High |
| Availability Impact | High | High |
CVSS v3 Vector
Red Hat CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
NVD CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Frequently Asked Questions
Why is Red Hat's CVSS v3 score or Impact different from other vendors?
For more information, see https://access.redhat.com/solutions/762393.
My product is listed as "Under investigation" or "Affected", when will Red Hat release a fix for this vulnerability?
- "Under investigation" doesn't necessarily mean that the product is affected by this vulnerability. It only means that our Analysis Team is still working on determining whether the product is affected and how it is affected.
- "Affected" means that our Analysis Team has determined that this product is affected by this vulnerability and might release a fix to address this in the near future.
What can I do if my product is listed as "Will not fix"?
Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
- Upgrade to a supported product version that includes a fix for this vulnerability (recommended).
- Apply a mitigation (if one exists).
- Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
What can I do if my product is listed as "Fix deferred"?
Available options depend mostly on the Impact of the vulnerability and the current Life Cycle phase of your product. Overall, you have the following options:
- Apply a mitigation (if one exists).
- Open a This content is not included.support case to request a prioritization of releasing a fix for this vulnerability.
- Red Hat Engineering focuses on addressing high-priority issues based on their complexity or limited lifecycle support. Therefore, lower-priority issues will not receive immediate fixes.
What is a mitigation?
I have a Red Hat product but it is not in the above list, is it affected?
Why is my security scanner reporting my product as vulnerable to this vulnerability even though my product version is fixed or not affected?
My product is listed as "Out of Support Scope". What does this mean?
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