CVE-2026-74425: afs: handle CB.InitCallBackState3 requests without a server record
In the Linux kernel, the following vulnerability has been resolved:
afs: handle CB.InitCallBackState3 requests without a server record
The cache manager callback path now attaches the server record to an incoming call through the rxrpc peer's app data. That association is not guaranteed to exist for every callback request, and most callback handlers already tolerate that case.
Make CB.InitCallBackState3 follow the same pattern by checking whether a server record was attached before using it. If the peer is not mapped to a server record, trace the request and ignore it, matching the existing behaviour for other unmatched callback requests.
This keeps the callback handler consistent with the rest of the cache manager service and avoids depending on peer state that may not be available for a given request.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
ubuntu/linux-aws-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1014.14~24.04.1 - Upgrade
Upgrade
ubuntu/linux-azure-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1017.17~24.04.1 - Upgrade
Upgrade
ubuntu/linux-azure-fde-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1016.16~24.04.1 - Upgrade
Upgrade
ubuntu/linux-gcp-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1014.14~24.04.1 - Upgrade
Upgrade
ubuntu/linux-hwe-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-38.38~24.04.4 - Upgrade
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ubuntu/linux-nvidia-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1024.25~24.04.1 - Upgrade
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ubuntu/linux-oracle-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1013.13~24.04.1 - Upgrade
Upgrade
ubuntu/linux-riscv-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-38.38.1~24.04.1 - Upgrade
Upgrade
ubuntu/linuxto a version that resolves this vulnerability.Fixed in 7.0.0-38.38 - Upgrade
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ubuntu/linux-awsto a version that resolves this vulnerability.Fixed in 7.0.0-1014.14 - Upgrade
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ubuntu/linux-azureto a version that resolves this vulnerability.Fixed in 7.0.0-1017.17 - Upgrade
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ubuntu/linux-azure-fdeto a version that resolves this vulnerability.Fixed in 7.0.0-1016.16 - Upgrade
Upgrade
ubuntu/linux-gcpto a version that resolves this vulnerability.Fixed in 7.0.0-1014.14 - Upgrade
Upgrade
ubuntu/linux-gketo a version that resolves this vulnerability.Fixed in 7.0.0-1008.9 - Upgrade
Upgrade
ubuntu/linux-ibmto a version that resolves this vulnerability.Fixed in 7.0.0-1015.15 - Upgrade
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ubuntu/linux-nvidia-bosto a version that resolves this vulnerability.Fixed in 7.0.0-2022.23 - Upgrade
Upgrade
ubuntu/linux-oem-7.0to a version that resolves this vulnerability.Fixed in 7.0.0-1015.15 - Upgrade
Upgrade
ubuntu/linux-oracleto a version that resolves this vulnerability.Fixed in 7.0.0-1013.13 - Upgrade
Upgrade
ubuntu/linux-realtimeto a version that resolves this vulnerability.Fixed in 7.0.0-38.38.1 - Upgrade
Upgrade
ubuntu/linux-riscvto a version that resolves this vulnerability.Fixed in 7.0.0-38.38.1 - Compensating control
If the rxrpc peer is not mapped to a server record, trace the CB.InitCallBackState3 request and ignore it instead of using an unattached server record.
Event History
Frequently Asked Questions
What is the severity of CVE-2026-74425?
CVE-2026-74425 has a severity rating of 10, indicating a critical vulnerability.
What type of vulnerability is CVE-2026-74425?
CVE-2026-74425 is a kernel vulnerability in the Linux operating system, specifically related to AFS callback handling.
How do I fix CVE-2026-74425?
To fix CVE-2026-74425, update your Linux kernel to a version that addresses this vulnerability.
What systems are affected by CVE-2026-74425?
CVE-2026-74425 affects Linux systems utilizing the AFS file system in the kernel.
What are the potential impacts of CVE-2026-74425?
The potential impacts of CVE-2026-74425 include unauthorized access or exploitation of system resources due to improper handling of callback requests.