CVE-2026-74402
Received
Received - Intake
Improper Entropy Generation in Linux Kernel Atmel SHA204A Driver
Vulnerability report for CVE-2026-74402, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-15
Last updated on: 2026-08-15
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
crypto: atmel-sha204a - fix blocking and non-blocking rng logic
The blocking and non-blocking paths were failing to provide valid entropy
due to improper buffer management. Reading the buffer starting from byte 1,
only fetch the 32 bytes of random data from the return message.
Tested on an Atmel SHA204A device.
Before (here for blocking), tests showed repeatedly reading reduced bytes.
$ head -c 32 /dev/hwrng | hexdump -C
00000000 02 28 85 b3 47 40 f2 ee 00 00 00 00 00 00 00 00 |.(..G@..........|
00000010 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 |................|
00000020
After, the result will be similar to the following:
$ head -c 32 /dev/hwrng | hexdump -C
00000000 5a fc 3f 13 14 68 fe 06 68 0a bd 04 83 6e 09 69 |Z.?..h..h....n.i|
00000010 75 ff cf 87 10 84 3b c9 c1 df ae eb 45 53 4c c3 |u.....;.....ESL.|
00000020
CVSS Scores
EPSS Scores
| Probability: | |
| Percentile: |
Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| atmel | sha204a | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
