CVE-2026-46081 (GCVE-0-2026-46081)
Vulnerability from cvelistv5 – Published: 2026-05-27 12:58 – Updated: 2026-08-05 12:29
VLAI
EPSS
VEX
Title
crypto: acomp - fix wrong pointer stored by acomp_save_req()
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.
Severity
7.8 (High)
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
64929fe8c0a43508eee952cf57903a61c52601e7 , < 343a5bf68a8ff9affcf2b70677ea4cf40c195ee4
(git)
Affected: 64929fe8c0a43508eee952cf57903a61c52601e7 , < 1a2785e5985627f2265ba7775949601a29ba0d1e (git) Affected: 64929fe8c0a43508eee952cf57903a61c52601e7 , < d7e20b9bd6c990773cf0c09e2642250b8a70263d (git) |
guessed | |
| Linux | Linux |
Affected:
6.16
Unaffected: 0 , < 6.16 (semver) Unaffected: 6.18.27 , ≤ 6.18.* (semver) Unaffected: 7.0.4 , ≤ 7.0.* (semver) Unaffected: 7.1 , ≤ * (original_commit_for_fix) |
guessed |
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"title": "crypto: acomp - fix wrong pointer stored by acomp_save_req()",
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"lastModified": "2026-06-24T17:20:20.110",
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"title": "kernel: crypto: acomp - fix wrong pointer stored by acomp_save_req()",
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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