Local system crash via unguarded CM3 access
Published Apr 3, 2026 · Updated Apr 3, 2026
NULL pointer dereference in the Linux Kernel mvpp2 driver allows local users to crash the system by changing an interface MTU. The mvpp2_bm_switch_buffers() function calls mvpp2_bm_pool_update_priv_fc() without checking global_tx_fc, causing CM3 register access through a NULL cm3_base when CM3 SRAM is absent. Reaching the crash requires local low-privileged access to change an mvpp2 interface MTU across the jumbo-frame threshold on affected hardware.
Summary
What happened
NULL pointer dereference in the Linux Kernel mvpp2 driver allows local users to crash the system by changing an interface MTU. The mvpp2_bm_switch_buffers() function calls mvpp2_bm_pool_update_priv_fc() without checking global_tx_fc, causing CM3 register access through a NULL cm3_base when CM3 SRAM is absent. Reaching the crash requires local low-privileged access to change an mvpp2 interface MTU across the jumbo-frame threshold on affected hardware.
The record
- CVE
- CVE-2026-23438
- Published
- Apr 3, 2026
- Updated
- Apr 3, 2026
- Vendor
- The Linux Kernel Organization
- Product
- Linux Kernel
- Classifications
- CWE-476, T1499
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Apr 3, 2026CVE publishedPublication date reported by the CVE source.
- Apr 3, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=3a616b92a9d17448d96a33bf58e69f01457fd43a <7bd20f4b3ef3044dc55acd5b8ef748a70d29d03f
- Affected versionversion=3a616b92a9d17448d96a33bf58e69f01457fd43a <7df2b50cae1a76cbb90b294f3edb61e3e10bf2e9
- Affected versionversion=3a616b92a9d17448d96a33bf58e69f01457fd43a <8a63baadf08453f66eb582fdb6dd234f72024723
- Affected versionversion=3a616b92a9d17448d96a33bf58e69f01457fd43a <8baced53a35fc9710f80d6ca016a2c418dc3231f
- Affected versionversion=3a616b92a9d17448d96a33bf58e69f01457fd43a <da089f74a993f846685067b14158cb41b879ff29
- Affected versionversion=3a616b92a9d17448d96a33bf58e69f01457fd43a <ff0c54f088f7ab91dbbf47cf8244460f99122750
- Affected versionversion=5.12
What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
What attackers are doing with it
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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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