CVE-2026-46081

CVE-2026-46081 is a high-severity vulnerability in Linux Linux Kernel with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Description

In the Linux kernel, the following vulnerability has been resolved: crypto: acomp - fix wrong pointer stored by acomp_save_req() acomp_save_req() stores &req->chain in req->base.data. When acomp_reqchain_done() is invoked on asynchronous completion, it receives &req->chain as the data argument but casts it directly to struct acomp_req. Since data points to the chain member, all subsequent field accesses are at a wrong offset, resulting in memory corruption. The issue occurs when an asynchronous hardware implementation, such as the QAT driver, completes a request that uses the DMA virtual address interface (e.g. acomp_request_set_src_dma()). This combination causes crypto_acomp_compress() to enter the acomp_do_req_chain() path, which sets acomp_reqchain_done() as the completion callback via acomp_save_req(). With KASAN enabled, this manifests as a general protection fault in acomp_reqchain_done(): general protection fault, probably for non-canonical address 0xe000040000000000 KASAN: probably user-memory-access in range [0x0000400000000000-0x0000400000000007] RIP: 0010:acomp_reqchain_done+0x15b/0x4e0 Call Trace: <IRQ> qat_comp_alg_callback+0x5d/0xa0 [intel_qat] adf_ring_response_handler+0x376/0x8b0 [intel_qat] adf_response_handler+0x60/0x170 [intel_qat] tasklet_action_common+0x223/0x820 handle_softirqs+0x1ab/0x640 </IRQ> Fix this by storing the request itself in req->base.data instead of &req->chain, so that acomp_reqchain_done() receives the correct pointer. Simplify acomp_restore_req() accordingly to access req->chain directly.

Frequently asked questions

What is CVE-2026-46081?
In the Linux kernel, the following vulnerability has been resolved: crypto: acomp - fix wrong pointer stored by acomp_save_req() acomp_save_req() stores &req->chain in req->base.data. When acomp_reqchain_done() is invoked on asynchronous completion, it receives &req->chain as the data argument but casts it directly to struct acomp_req. Since data points to the chain member, all subsequent field accesses are at a wrong offset, resulting in memory corruption. The issue occurs when an asynchronous hardware implementation, such as the QAT driver, completes a request that uses the DMA virtual address interface (e.g. acomp_request_set_src_dma()). This combination causes crypto_acomp_compress() to enter the acomp_do_req_chain() path, which sets acomp_reqchain_done() as the completion callback via acomp_save_req(). With KASAN enabled, this manifests as a general protection fault in acomp_reqchain_done(): general protection fault, probably for non-canonical address 0xe000040000000000 KASAN: probably user-memory-access in range [0x0000400000000000-0x0000400000000007] RIP: 0010:acomp_reqchain_done+0x15b/0x4e0 Call Trace: <IRQ> qat_comp_alg_callback+0x5d/0xa0 [intel_qat] adf_ring_response_handler+0x376/0x8b0 [intel_qat] adf_response_handler+0x60/0x170 [intel_qat] tasklet_action_common+0x223/0x820 handle_softirqs+0x1ab/0x640 </IRQ> Fix this by storing the request itself in req->base.data instead of &req->chain, so that acomp_reqchain_done() receives the correct pointer. Simplify acomp_restore_req() accordingly to access req->chain directly.
How severe is CVE-2026-46081?
CVE-2026-46081 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2026-46081 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-46081?
CVE-2026-46081 affects Linux Linux Kernel. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-46081?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2026-46081 have an EU (EUVD) identifier?
Yes. CVE-2026-46081 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-32464.
When was CVE-2026-46081 published?
CVE-2026-46081 was published on 2026-05-27 and last updated on 2026-06-24.

References

Affected products (1)

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