Linux Kernel up to 7.3.0 Keyring Index information disclosure

CVSS Meta Temp Score
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CTI Interest Score
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3.2$0-$5k0.84-

Summaryinfo

A vulnerability has been found in Linux Kernel up to 7.3.0 and classified as problematic. Affected is an unknown function of the component Keyring Index. This manipulation causes information disclosure. This vulnerability is handled as CVE-2026-99223. It is possible to launch the attack on the local host. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability was found in Linux Kernel up to 7.3.0. It has been declared as problematic. Affected by this vulnerability is an unknown part of the component Keyring Index. The manipulation with an unknown input leads to a information disclosure vulnerability. The CWE definition for the vulnerability is CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. As an impact it is known to affect confidentiality. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: keys: make keyring indexes independent of kernel addresses KEYCTL_READ returns the serial numbers in a keyring in associative-array traversal order. The first word of the index is a public, deterministic hash of the type pointer, domain pointer and description. An unprivileged user can therefore insert keys with known descriptions, predict their order for each possible KASLR slide, and recover the kernel image address. On an x86-64 build with 16 MiB alignment, 45 user keys suffice to distinguish the candidate slides. Remove the addresses from the whole index, not just its first hash word. Assign each key type and domain a nonzero 64-bit ID and hash those IDs and the description with a once-initialized SipHash key. Use the full IDs in the later index chunks as well. Truncating or hashing the IDs there would lose the guarantee that distinct type/domain/description tuples have a differing index bit. Allocate IDs lazily since private key types need not be registered. Cache them in the index key so tree walks and copies of an existing index do not need to dereference a type descriptor that may have been unregistered. Keep the 32-bit chunk layout and diff_objects() bit offsets consistent, and retain the separate root slot for keyrings used by recursive search. The key comparison, permissions and userspace data format are unchanged; only the address-dependent in-memory ordering is replaced.

The advisory is shared at git.kernel.org. This vulnerability is known as CVE-2026-99223 since 09/25/2026. The exploitation appears to be easy. An attack has to be approached locally. Neither technical details nor an exploit are publicly available. MITRE ATT&CK project uses the attack technique T1592 for this issue.

Upgrading to version 5.10.273, 5.15.224, 6.1.191, 6.6.161, 6.12.115, 6.18.60, 7.2.14 or 7.3.1 eliminates this vulnerability. Applying the patch 9ebe824d55983c9f063a2c9ef1a08b29812d406f/e108b22999edbc6f431466baf6b2016c19b7ed31/9f084ef0beb68091e96ab96f0e95579aac8a77f9/8451d4a4c43127c3b9fdf9fc9ff3fea5539a61f9/13fc051269d670810d9e314061b61c6dd06116a0/61ac0585d9f4344d3dfb84b5edff1fee7d532897/84f7c699f8d139f743c7dc11ef41d085690955bb/a113eba06bd1183c614d7994864d6e7054140cb9 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: 3.3
VulDB Meta Temp Score: 3.2

VulDB Base Score: 3.3
VulDB Temp Score: 3.2
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: Information disclosure
CWE: CWE-200 / CWE-284 / CWE-266
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 5.10.273/5.15.224/6.1.191/6.6.161/6.12.115/6.18.60/7.2.14/7.3.1
Patch: 9ebe824d55983c9f063a2c9ef1a08b29812d406f/e108b22999edbc6f431466baf6b2016c19b7ed31/9f084ef0beb68091e96ab96f0e95579aac8a77f9/8451d4a4c43127c3b9fdf9fc9ff3fea5539a61f9/13fc051269d670810d9e314061b61c6dd06116a0/61ac0585d9f4344d3dfb84b5edff1fee7d532897/84f7c699f8d139f743c7dc11ef41d085690955bb/a113eba06bd1183c614d7994864d6e7054140cb9

Timelineinfo

09/25/2026 CVE reserved
11/02/2026 +38 days Advisory disclosed
11/02/2026 +0 days VulDB entry created
11/02/2026 +0 days VulDB entry last update

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CNA: Linux
CVE: CVE-2026-99223 (🔒)

GCVE (CVE): GCVE-0-2026-99223
GCVE (VulDB): GCVE-100-429901

Entryinfo

Created: 11/02/2026 17:22
Changes: 11/02/2026 17:22 (58)
Complete: 🔍
Cache ID: 216::103

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