CVE-2026-99225: Linux Vulnerability

Description

In the Linux kernel, the following vulnerability has been resolved: keys: Check the authorization payload in process keyring searches An authorization payload and its saved credentials must remain valid while search_process_keyrings_rcu() searches the requestor's keyrings. The function validates the authorization key, then separately loads payload.data[0] and unconditionally reads rka->cred. Validation does not prevent request_key_auth_revoke() from clearing the payload. A request-key helper can assume authority and fork a descendant that inherits the authorization key. If the descendant misses in its own keyrings, it falls back to the saved requestor credentials. Successful target instantiation invalidates the authorization key without clearing the payload. After the helper exits, UMH_WAIT_PROC returns to the requester, which calls complete_request_key() and revokes that key. With the descendant paused after validation, the paths can interleave as follows: 1. The descendant enters search_process_keyrings_rcu() under RCU and key_validate() succeeds. 2. The helper instantiates the target, invalidates the authorization key, and exits. 3. The requester resumes from UMH_WAIT_PROC, calls complete_request_key(), and revokes the authorization key. request_key_auth_revoke() sets its payload pointer to NULL. 4. The descendant loads NULL and dereferences rka->cred. This NULL dereference can oops the kernel. RCU delays payload disposal but does not prevent the pointer from being cleared. Load the payload with dereference_key_rcu() and require a non-NULL result before validating the authorization key and searching its saved credentials. A non-NULL payload and its credentials remain alive for the caller's RCU read-side section; a cleared payload skips the fallback search and follows the existing error selection. KASAN report as below: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] RIP: 0010:search_process_keyrings_rcu+0x32b/0x790

Metrics

EPSS Probability

0.17%

5.7th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

Vendor	Product	Versions
Linux	Linux	>= e59428f721ee096d8a020504ea908a6f0d952735, < 14fb6fad526b35a7ebd121f1dd313abe652e0aa6; >= e59428f721ee096d8a020504ea908a6f0d952735, < 458cf9715af6aff3ac8d2ec60bd59e9d6236fd0f; >= e59428f721ee096d8a020504ea908a6f0d952735, < 7d3d2fffe933e538472ccafe5bbc7109488b9ce3; >= e59428f721ee096d8a020504ea908a6f0d952735, < 26949c2e4c461e9e620e935bc22717f36a40b615; >= e59428f721ee096d8a020504ea908a6f0d952735, < 984a178d54515779a1bee100b92a6cee8777c830; >= e59428f721ee096d8a020504ea908a6f0d952735, < b86db7993051d05810601654e886a1e78e1fa495; >= e59428f721ee096d8a020504ea908a6f0d952735, < b4dfda438fee3c6faa15d9b421c373de6a0e476f; >= e59428f721ee096d8a020504ea908a6f0d952735, < 49f4e768540d25d8852ef750313afda6a4774871; >= e59428f721ee096d8a020504ea908a6f0d952735, < 0a0ec45bf577a9b4d4960567f20d3877ef480de9
Linux	Linux	5.3

References

Timeline

Published: Nov 2, 2026
Last Modified: Nov 3, 2026
Status: Received

Frequently Asked Questions

What is CVE-2026-99225?

In the Linux kernel, the following vulnerability has been resolved: keys: Check the authorization payload in process keyring searches An authorization payload and its saved credentials must remain valid while search_process_keyrings_rcu() searches the requestor's keyrings. The function validates the authorization key, then separately loads payload.data[0] and unconditionally reads rka->cred. Validation does not prevent request_key_auth_revoke() from clearing the payload. A request-key helper can assume authority and fork a descendant that inherits the authorization key. If the descendant misses in its own keyrings, it falls back to the saved requestor credentials. Successful target instantiation invalidates the authorization key without clearing the payload. After the helper exits, UMH_WAIT_PROC returns to the requester, which calls complete_request_key() and revokes that key. With the descendant paused after validation, the paths can interleave as follows: 1. The descendant enters search_process_keyrings_rcu() under RCU and key_validate() succeeds. 2. The helper instantiates the target, invalidates the authorization key, and exits. 3. The requester resumes from UMH_WAIT_PROC, calls complete_request_key(), and revokes the authorization key. request_key_auth_revoke() sets its payload pointer to NULL. 4. The descendant loads NULL and dereferences rka->cred. This NULL dereference can oops the kernel. RCU delays payload disposal but does not prevent the pointer from being cleared. Load the payload with dereference_key_rcu() and require a non-NULL result before validating the authorization key and searching its saved credentials. A non-NULL payload and its credentials remain alive for the caller's RCU read-side section; a cleared payload skips the fallback search and follows the existing error selection. KASAN report as below: Oops: general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] RIP: 0010:search_process_keyrings_rcu+0x32b/0x790

How severe is CVE-2026-99225?

Severity scoring for CVE-2026-99225 is pending analysis. The EPSS model estimates a 0.17% probability of exploitation in the next 30 days.

How do I fix CVE-2026-99225?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

How Strix Helps

Related CVEs from 2026

View all 2026CVEs →