Review reviewHigh

CVE-2025-40129

Linux

In the Linux kernel, the following vulnerability has been resolved: sunrpc: fix null pointer dereference on zero-length checksum In xdr_stream_decode_opaque_auth(), zero-length checksum.len causes checksum.data to be set to NULL. This triggers a NPD when accessing checksum.data in gss_krb5_verify_mic_v2(). This patch ensures that the value of checksum.len is not less than XDR_UNIT.

CVSS: 7.5
EPSS: 0.52%
CISA KEV: Not listed
Published: 2025.11.12

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.52%

Technical severityCVSS 7.5

Vulnerability overview

Affected product and versions

Product: Linux
Affected versions: >= 0653028e8f1c97fec30710813a001ad8a2ec34f4 < 81cec07d303186d0d8c623ef8b5ecd3b81e94cf6, >= 0653028e8f1c97fec30710813a001ad8a2ec34f4 < affc03d44921f493deaae1d33151e3067a6f9f8f, >= 0653028e8f1c97fec30710813a001ad8a2ec34f4 < ab9a70cd2386a0d70c164b0905dd66bc9af52e77, >= 0653028e8f1c97fec30710813a001ad8a2ec34f4 < 6df164e29bd4e6505c5a2e0e5f1e1f6957a16a42, >= 6.3
Fixed versions: No verified fixed-version field is available yet

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that Linux and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE: Not available