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Fencer Vulns
high 7.8

CVE-2026-46081 json

crypto: acomp - fix wrong pointer stored by acomp_save_req()

published 2026-05-27 5 mo ago modified 2026-08-05 3 mo ago also EUVD-2026-32464

cvss
7.8
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 5%
public exploits
0
none known

Summary

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.

Patch / fix

  • Linux Linux 6.18.27, 7.0.4, 7.1
  • linux Debian 14 7.0.4-1

debian advisories DEBIAN-CVE-2026-46081

  • linux Ubuntu 26.04 LTS 7.0.0-27.27
  • linux-aws Ubuntu 26.04 LTS 7.0.0-1008.8
  • linux-gcp Ubuntu 26.04 LTS 7.0.0-1007.7
  • linux-ibm Ubuntu 26.04 LTS 7.0.0-1009.9
  • linux-azure Ubuntu 26.04 LTS 7.0.0-1010.10
  • linux-raspi Ubuntu 26.04 LTS 7.0.0-1014.14
  • linux-riscv Ubuntu 26.04 LTS 7.0.0-27.27.1
  • linux-nvidia Ubuntu 26.04 LTS 7.0.0-1013.13

ubuntu advisories UBUNTU-CVE-2026-46081

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

  • kernel-source openSUSE Tumbleweed 7.0.11-1.1

opensuse advisories openSUSE-SU-2026:10954-1

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-46081 updated

kernel: crypto: acomp - fix wrong pointer stored by acomp_save_req()

  • Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

Exploit prediction

0.17% chance of exploitation in the next 30 days, higher than 5% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 7.8 CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected products

  • Linux Linux

Classification

Weakness
Technology feeds

References

Sources

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