Linux Kernel up to 6.18.51/7.2.5 xilinx-trng xtrng_readblock32 error condition

CVSS Meta Temp Score
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CTI Interest Score
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7.8$0-$5k0.00-

Summaryinfo

A vulnerability, which was classified as very critical, was found in Linux Kernel up to 6.18.51/7.2.5. This vulnerability affects the function xtrng_readblock32 of the component xilinx-trng. Such manipulation leads to error condition. This vulnerability is traded as CVE-2026-93157. An attack has to be approached locally. There is no exploit available. You should upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as very critical, has been found in Linux Kernel up to 6.18.51/7.2.5. Affected by this issue is the function xtrng_readblock32 of the component xilinx-trng. The manipulation with an unknown input leads to a error condition vulnerability. Using CWE to declare the problem leads to CWE-391. [PLANNED FOR DEPRECATION. SEE MAINTENANCE NOTES AND CONSIDER CWE-252, CWE-248, OR CWE-1069.] Ignoring exceptions and other error conditions may allow an attacker to induce unexpected behavior unnoticed. Impacted is confidentiality, integrity, and availability. CVE summarizes:

In the Linux kernel, the following vulnerability has been resolved: hwrng: xilinx-trng - propagate timeout before any data is read xtrng_readblock32() polls for 16-byte chunks but returns the number of bytes read even when the first poll times out. Its caller then treats a zero return as a short successful read, and partial reads for full 32-byte blocks can make the tail copy use a fixed block offset rather than the amount already produced. Return the poll error when no data has been read, preserve partial positive returns after some data is available, stop the generator on all collection exits, and append tail bytes at the current output count.

The advisory is available at git.kernel.org. This vulnerability is handled as CVE-2026-93157 since 09/17/2026. The exploitation is known to be easy. Local access is required to approach this attack. Additional levels of successful authentication are needed for exploitation. 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 09/17/2026).

Upgrading to version 6.18.52, 7.2.6 or 7.3-rc1 eliminates this vulnerability. Applying the patch 62219775a07ce0bd8085852f3d1e2d772bf6fdec/bdc3b37a935f28c3e9eb2f6e889b4644d859fb08/ba088974419326daf46c5dc03e2cf6ab6ab701f7 is able to eliminate this problem. The best possible mitigation is suggested to be upgrading to the latest version.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.2
VulDB Meta Temp Score: 7.8

VulDB Base Score: 8.2
VulDB Temp Score: 7.8
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: Error condition
CWE: CWE-391
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: 62219775a07ce0bd8085852f3d1e2d772bf6fdec/bdc3b37a935f28c3e9eb2f6e889b4644d859fb08/ba088974419326daf46c5dc03e2cf6ab6ab701f7

Timelineinfo

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

Sourcesinfo

Vendor: kernel.org

Advisory: git.kernel.org
Status: Confirmed

CVE: CVE-2026-93157 (🔒)
GCVE (CVE): GCVE-0-2026-93157
GCVE (VulDB): GCVE-100-407234

Entryinfo

Created: 09/17/2026 23:58
Changes: 09/17/2026 23:58 (60)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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