Linux Kernel up to 5.15.112/6.1.29/6.3.3 SUNRPC svc_defer double free

Summaryinfo

A vulnerability, which was classified as critical, has been found in Linux Kernel up to 5.15.112/6.1.29/6.3.3. Affected is the function svc_defer of the component SUNRPC. Performing a manipulation results in double free. This vulnerability is reported as CVE-2023-54269. No exploit exists. It is advisable to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, was found in Linux Kernel up to 5.15.112/6.1.29/6.3.3. This affects the function svc_defer of the component SUNRPC. The manipulation with an unknown input leads to a double free vulnerability. CWE is classifying the issue as CWE-415. The product calls free() twice on the same memory address, potentially leading to modification of unexpected memory locations. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: SUNRPC: double free xprt_ctxt while still in use When an RPC request is deferred, the rq_xprt_ctxt pointer is moved out of the svc_rqst into the svc_deferred_req. When the deferred request is revisited, the pointer is copied into the new svc_rqst - and also remains in the svc_deferred_req. In the (rare?) case that the request is deferred a second time, the old svc_deferred_req is reused - it still has all the correct content. However in that case the rq_xprt_ctxt pointer is NOT cleared so that when xpo_release_xprt is called, the ctxt is freed (UDP) or possible added to a free list (RDMA). When the deferred request is revisited for a second time, it will reference this ctxt which may be invalid, and the free the object a second time which is likely to oops. So change svc_defer() to *always* clear rq_xprt_ctxt, and assert that the value is now stored in the svc_deferred_req.

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2023-54269 since 12/30/2025. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 04/27/2026).

The vulnerability scanner Nessus provides a plugin with the ID 281548 (Linux Distros Unpatched Vulnerability : CVE-2023-54269), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 5.15.113, 6.1.30 or 6.3.4 eliminates this vulnerability. Applying the patch 7851771789e87108a92697194105ef0c9307dc5e/fd86534872f445f54dc01e7db001e25eadf063a8/e0c648627322a4c7e018e5c7f837c3c03e297dbb/eb8d3a2c809abd73ab0a060fe971d6b9019aa3c1 is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the databases at Tenable (281548) and CERT Bund (WID-SEC-2025-2941). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

• Debian Linux
• Amazon Linux 2
• IBM Power Hardware Management Console
• Red Hat Enterprise Linux
• Ubuntu Linux
• SUSE Linux
• Oracle Linux
• Open Source Linux Kernel
• RESF Rocky Linux
• IBM DataPower Gateway

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 5.15.112
• 6.1.0
• 6.1.1
• 6.1.2
• 6.1.3
• 6.1.4
• 6.1.5
• 6.1.6
• 6.1.7
• 6.1.8
• 6.1.9
• 6.1.10
• 6.1.11
• 6.1.12
• 6.1.13
• 6.1.14
• 6.1.15
• 6.1.16
• 6.1.17
• 6.1.18
• 6.1.19
• 6.1.20
• 6.1.21
• 6.1.22
• 6.1.23
• 6.1.24
• 6.1.25
• 6.1.26
• 6.1.27
• 6.1.28
• 6.1.29
• 6.3.0
• 6.3.1
• 6.3.2
• 6.3.3

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

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