Linux Kernel up to 6.18.43/7.1.7 riscv vec_check_unaligned_access_speed_all_cpus memory corruption

CVSS Meta Temp Score CVSS is a standardized scoring system to determine possibilities of attacks. The Temp Score considers temporal factors like disclosure, exploit and countermeasures. The unique Meta Score calculates the average score of different sources to provide a normalized scoring system.	Current Exploit Price (≈) Our analysts are monitoring exploit markets and are in contact with vulnerability brokers. The range indicates the observed or calculated exploit price to be seen on exploit markets. A good indicator to understand the monetary effort required for and the popularity of an attack.	CTI Interest Score Our Cyber Threat Intelligence team is monitoring different web sites, mailing lists, exploit markets and social media networks. The CTI Interest Score identifies the interest of attackers and the security community for this specific vulnerability in real-time. A high score indicates an elevated risk to be targeted for this vulnerability.
4.2	$0-$5k	0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in Linux Kernel up to 6.18.43/7.1.7. The affected element is the function vec_check_unaligned_access_speed_all_cpus of the component riscv. Executing a manipulation can lead to memory corruption. This vulnerability is tracked as CVE-2026-80688. The attack is restricted to local execution. No exploit exists.

Detailsinfo

A vulnerability classified as problematic was found in Linux Kernel up to 6.18.43/7.1.7. This vulnerability affects the function vec_check_unaligned_access_speed_all_cpus of the component riscv. The manipulation with an unknown input leads to a memory corruption vulnerability. The CWE definition for the vulnerability is CWE-119. The product performs operations on a memory buffer, but it can read from or write to a memory location that is outside of the intended boundary of the buffer. As an impact it is known to affect integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: riscv: drop __init from vec_check_unaligned_access_speed_all_cpus This function runs within a kthread and need not necessarily finish before system finishes boot and free_initmem() unmaps the .init.text section. This function makes calls to SBI for probing unaligned access speed, and if this is slow for some reason (say some debug prints were added to SBI), the kthread can still be running at this point and result in an instruction page fault when trying to fetch from the freed region. [ 25.642087] Unable to handle kernel paging request at virtual address ffffffff80a04ef8 [ 25.646694] Current vec_check_unali pgtable: 4K pagesize, 48-bit VAs, pgdp=0x00004000316e9000 [ 25.653170] [ffffffff80a04ef8] pgd=000010004be7e401, p4d=000010004be7e401, pud=000010004be7e001, pmd=000010000c3000e3 [ 25.661244] Oops [#1] [ 25.662997] Modules linked in: [ 25.665357] CPU: 3 UID: 0 PID: 42 Comm: vec_check_unali Not tainted 7.0.0-tt-blackhole-asrinivasan-00007-g30ff73f18211 #570 PREEMPTLAZY [ 25.674669] Hardware name: Tenstorrent Blackhole (DT) [ 25.678545] epc : vec_check_unaligned_access_speed_all_cpus+0x18/0x2c [ 25.683458] ra : vec_check_unaligned_access_speed_all_cpus+0x18/0x2c [ 25.688372] epc : ffffffff80a04ef8 ra : ffffffff80a04ef8 sp : ffff8f8000203e20 [ 25.693874] gp : ffffffff814dc168 tp : ffffaf8001ad9900 t0 : 0000000000000000 [ 25.699401] t1 : fffffffffffffff0 t2 : ffffaf8001ad9a10 s0 : ffff8f8000203e30 [ 25.704912] s1 : ffffaf80018dc780 a0 : 0000000000000000 a1 : 0000000000000002 [ 25.710407] a2 : 00000000000001f0 a3 : 0000000000000018 a4 : 0000000000000000 [ 25.715917] a5 : 0000000000000000 a6 : ffffaf8001c03d98 a7 : ffffaf8001c03e30 [ 25.721419] s2 : ffff8f8000023c98 s3 : ffffaf8001aa1240 s4 : ffffffff80a04ee0 [ 25.726937] s5 : 0000000000000000 s6 : 0000000000000000 s7 : 0000000000000000 [ 25.732450] s8 : 0000000000000000 s9 : 0000000000000000 s10: 0000000000000000 [ 25.737944] s11: 0000000000000000 t3 : 0000000000000002 t4 : 0000000000000402 [ 25.743481] t5 : 0000000000000040 t6 : 0000000000000004 ssp : 0000000000000000 [ 25.749024] status: 0000000200000120 badaddr: ffffffff80a04ef8 cause: 000000000000000c [ 25.755060] [<ffffffff80a04ef8>] vec_check_unaligned_access_speed_all_cpus+0x18/0x2c [ 25.760964] [<ffffffff80047a10>] kthread+0xd8/0xfc [ 25.764660] [<ffffffff80010c48>] ret_from_fork_kernel+0x18/0x1c4 [ 25.769220] [<ffffffff80895fe6>] ret_from_fork_kernel_asm+0x16/0x18 [ 25.774018] Code: cccc cccc cccc cccc cccc cccc cccc cccc cccc cccc (cccc) cccc Drop __init from its signature so that this doesn't happen.

The advisory is available at git.kernel.org. This vulnerability was named CVE-2026-80688 since 08/26/2026. The exploitation appears to be easy. Local access is required to approach this attack. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 08/28/2026).

Upgrading to version 6.18.44 or 7.1.8 eliminates this vulnerability. Applying the patch 01bd01b61ad9ea917e5629a7f14f57a8af0543bb/25f228e6ac573884a3d7078cc2b3312b8db59eea/f51fed61eea0daba2f95f1a6074085e4cd513c7b is able to eliminate this problem.

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Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 6.18.0
• 6.18.1
• 6.18.2
• 6.18.3
• 6.18.4
• 6.18.5
• 6.18.6
• 6.18.7
• 6.18.8
• 6.18.9
• 6.18.10
• 6.18.11
• 6.18.12
• 6.18.13
• 6.18.14
• 6.18.15
• 6.18.16
• 6.18.17
• 6.18.18
• 6.18.19
• 6.18.20
• 6.18.21
• 6.18.22
• 6.18.23
• 6.18.24
• 6.18.25
• 6.18.26
• 6.18.27
• 6.18.28
• 6.18.29
• 6.18.30
• 6.18.31
• 6.18.32
• 6.18.33
• 6.18.34
• 6.18.35
• 6.18.36
• 6.18.37
• 6.18.38
• 6.18.39
• 6.18.40
• 6.18.41
• 6.18.42
• 6.18.43
• 7.1.0
• 7.1.1
• 7.1.2
• 7.1.3
• 7.1.4
• 7.1.5
• 7.1.6
• 7.1.7

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 4.4
VulDB Meta Temp Score: 4.2

VulDB Base Score: 4.4
VulDB Temp Score: 4.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AV	AC	Au	C	I	A
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳
💳	💳	💳	💳	💳	💳

Vector	Complexity	Authentication	Confidentiality	Integrity	Availability
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock
Unlock	Unlock	Unlock	Unlock	Unlock	Unlock

VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Memory corruption
CWE: CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Today	Unlock	Unlock	Unlock	Unlock

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.18.44/7.1.8
Patch: 01bd01b61ad9ea917e5629a7f14f57a8af0543bb/25f228e6ac573884a3d7078cc2b3312b8db59eea/f51fed61eea0daba2f95f1a6074085e4cd513c7b

Timelineinfo

08/26/2026 CVE reserved
08/28/2026 +2 days Advisory disclosed
08/28/2026 +0 days VulDB entry created
08/28/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-80688 (🔒)
GCVE (CVE): GCVE-0-2026-80688
GCVE (VulDB): GCVE-100-396622

Entryinfo

Created: 08/28/2026 10:53
Changes: 08/28/2026 10:53 (59)
Complete: 🔍
Cache ID: 216::103

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Discussion

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