Linux Kernel up to 6.18.51/7.2.5 RSI Attestation Token Init rsi_cmds.h rsi_attestation_token_init out-of-bounds write

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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8.4$0-$5k0.00+

Summaryinfo

A vulnerability has been found in Linux Kernel up to 6.18.51/7.2.5 and classified as very critical. The impacted element is the function rsi_attestation_token_init of the file arch/arm64/include/asm/rsi_cmds.h of the component RSI Attestation Token Init. Performing a manipulation results in out-of-bounds write. This vulnerability was named CVE-2026-93266. The attack needs to be approached locally. There is no available exploit. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 6.18.51/7.2.5. It has been classified as very critical. This affects the function rsi_attestation_token_init of the file arch/arm64/include/asm/rsi_cmds.h of the component RSI Attestation Token Init. The manipulation with an unknown input leads to a out-of-bounds write vulnerability. CWE is classifying the issue as CWE-787. The product writes data past the end, or before the beginning, of the intended buffer. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: arm64: RSI: fix field-spanning write warning in attestation token init The challenge is passed in registers a1 through a8. However, copying to &regs.a1 makes FORTIFY treat the destination as the single a1 field, resulting in a field-spanning write warning. [1] Overlay the SMCCC register structure with an RSI-specific argument layout and copy the challenge into an explicit 64-byte array. This keeps the existing a1-a8 argument encoding while giving the copy a correctly sized destination object. [1] memcpy: detected field-spanning write (size 64) of single field "&regs.a1" at ./arch/arm64/include/asm/rsi_cmds.h:119 (size 8) WARNING: ./arch/arm64/include/asm/rsi_cmds.h:119 at rsi_attestation_token_init+0xdc/0xf8 [arm_cca_guest], CPU#0: cat/3314

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2026-93266 since 09/17/2026. The exploitability is told to be easy. An attack has to be approached locally. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/24/2026).

Upgrading to version 6.18.52, 7.2.6 or 7.3-rc1 eliminates this vulnerability. Applying the patch e505092cb200d430d5b8d8d3e926d45f29474ba3/d29a8ee271da17b5e32d7a76a9c78d43f66447ca/221049874b6a78c7d87bc826581b0695cd338e2b is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

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Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.8
VulDB Meta Temp Score: 8.4

VulDB Base Score: 8.8
VulDB Temp Score: 8.4
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

Class: Out-of-bounds write
CWE: CWE-787 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

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

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Kernel 6.18.52/7.2.6/7.3-rc1
Patch: e505092cb200d430d5b8d8d3e926d45f29474ba3/d29a8ee271da17b5e32d7a76a9c78d43f66447ca/221049874b6a78c7d87bc826581b0695cd338e2b

Timelineinfo

09/17/2026 CVE reserved
09/24/2026 +7 days Advisory disclosed
09/24/2026 +0 days VulDB entry created
09/24/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-93266 (🔒)
GCVE (CVE): GCVE-0-2026-93266
GCVE (VulDB): GCVE-100-409713

Entryinfo

Created: 09/24/2026 20:24
Changes: 09/24/2026 20:24 (60)
Complete: 🔍
Cache ID: 216::103

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