Skip to main content

Linux Kernel CVE-2025-40129

HIGH
2025-11-12 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Denial Of Service Linux Red Hat Suse
7.5
CVSS 3.1 · Vendor: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Share

Severity by source

Vendor (416baaa9-dc9f-4396-8d5f-8c081fb06d67) PRIMARY
7.5 HIGH
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
vuln.today AI
7.5 HIGH

Remotely reachable SUNRPC service needs no auth or interaction (AV:N/AC:L/PR:N/UI:N); NULL-deref causes kernel panic, so availability-only impact (A:H, C:N/I:N).

3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
4.0 AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
SUSE
HIGH
qualitative
Red Hat
4.7 MEDIUM
qualitative

Primary rating from Vendor (416baaa9-dc9f-4396-8d5f-8c081fb06d67).

CVSS VectorVendor: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

Lifecycle Timeline

7
Analysis Updated
Jul 30, 2026 - 09:10 vuln.today
v3 (cvss_changed)
Analysis Updated
Jul 30, 2026 - 09:09 vuln.today
v2 (cvss_changed)
Re-analysis Queued
Jul 30, 2026 - 06:37 vuln.today
cvss_changed
CVSS changed
Jul 30, 2026 - 06:37 NVD
7.5 (HIGH)
Patch released
Mar 28, 2026 - 19:31 nvd
Patch available
Analysis Generated
Mar 28, 2026 - 19:21 vuln.today
CVE Published
Nov 12, 2025 - 11:15 nvd
N/A

DescriptionCVE.org

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.

AnalysisAI

Denial of service in the Linux kernel's SUNRPC/GSS-Kerberos (krb5) implementation allows remote attackers to crash the system via a zero-length RPCSEC_GSS checksum. When xdr_stream_decode_opaque_auth() decodes an auth token whose checksum length is zero, checksum.data is set to NULL, and gss_krb5_verify_mic_v2() then dereferences that NULL pointer, triggering a kernel panic. The CVSS 7.5 vector (AV:N/AC:L/PR:N/UI:N with A:H only) reflects availability-only impact; EPSS is very low (0.03%, 10th percentile) and there is no public exploit identified at time of analysis, though a vendor patch is available.

Technical ContextAI

The flaw lives in the kernel's SUNRPC layer, which underpins NFS and other RPC services and handles RPCSEC_GSS authentication using the Kerberos 5 (krb5) security mechanism. During inbound message processing, the XDR (External Data Representation) decoder xdr_stream_decode_opaque_auth() parses the opaque authenticator, including the integrity checksum (MIC). If the encoded checksum length is zero, the decoder returns a checksum structure with .len = 0 and .data = NULL. The subsequent MIC verification routine gss_krb5_verify_mic_v2() assumes a valid buffer and dereferences checksum.data, causing a NULL pointer dereference (a CWE-476-class root cause, though the input lists CWE as N/A). The fix enforces that checksum.len is not smaller than XDR_UNIT (4 bytes), rejecting the malformed token before it reaches the verification path.

Affected ProductsAI

The affected product is the Linux kernel, specifically builds that include the SUNRPC GSS/krb5 subsystem. Exact vulnerable version ranges are not enumerated in the provided NVD data (CWE and per-commit version metadata are listed as None), so affected versions should be derived from the stable-tree fix commits (6df164e29bd4, 81cec07d3031, ab9a70cd2386, affc03d44921 at git.kernel.org) and downstream advisories. Canonical/Ubuntu confirms real-world exposure and provides fixed-package mappings in USN-8125-1 (https://ubuntu.com/security/notices/USN-8125-1) and USN-8126-1 (https://ubuntu.com/security/notices/USN-8126-1). No CPE strings were provided in the input, so precise product/version CPE matching could not be performed here.

RemediationAI

Patch available per vendor advisory: update the kernel to a fixed stable release incorporating the SUNRPC fix (upstream stable commits 6df164e29bd4, 81cec07d3031, ab9a70cd2386, and affc03d44921 at git.kernel.org), or, on Ubuntu, apply the fixed kernel packages described in USN-8125-1 (https://ubuntu.com/security/notices/USN-8125-1) and USN-8126-1 (https://ubuntu.com/security/notices/USN-8126-1) and reboot into the patched kernel. Exact upstream-tagged release version numbers were not provided in the input, so confirm the precise fixed version against your distribution's advisory before deployment. If immediate patching is not possible, reduce the attack surface by restricting or disabling RPCSEC_GSS/krb5-authenticated RPC exposure - for example, limit Kerberized NFS/RPC services to trusted network segments via firewall rules on the relevant RPC ports and mountd/rpcbind, or temporarily disable krb5 RPC auth where it is not required; the trade-off is loss of Kerberos-secured NFS functionality for affected clients, so apply this only as an interim control until the kernel is updated.

Same technique Denial Of Service

View all
CVE-2015-5119 CRITICAL POC
9.8
CVE-2011-2462 CRITICAL POC
9.8
CVE-2011-0611 HIGH POC
8.8
CVE-2012-1889 HIGH POC
8.8
CVE-2012-0507 CRITICAL POC
9.8
CVE-2014-1761 HIGH POC
7.8
CVE-2015-5122 CRITICAL POC
9.8
CVE-2011-0609 HIGH POC
7.8

Vendor StatusVendor

SUSE

Severity: Important
Product Status
Container suse/hpc/warewulf4-x86_64/sle-hpc-node:latest Image SLES15-SP6 Image SLES15-SP6-BYOS Image SLES15-SP6-BYOS-Azure Image SLES15-SP6-BYOS-EC2 Image SLES15-SP6-BYOS-GCE Image SLES15-SP6-CHOST-BYOS Image SLES15-SP6-CHOST-BYOS-Aliyun Image SLES15-SP6-CHOST-BYOS-Azure Image SLES15-SP6-CHOST-BYOS-EC2 Image SLES15-SP6-CHOST-BYOS-GCE Image SLES15-SP6-CHOST-BYOS-GDC Image SLES15-SP6-CHOST-BYOS-SAP-CCloud Image SLES15-SP6-EC2 Image SLES15-SP6-EC2-ECS-HVM Image SLES15-SP6-GCE Image SLES15-SP6-HPC-BYOS Image SLES15-SP6-HPC-BYOS-Azure Image SLES15-SP6-HPC-BYOS-EC2 Image SLES15-SP6-HPC-BYOS-GCE Image SLES15-SP6-HPC-EC2 Image SLES15-SP6-HPC-GCE Image SLES15-SP6-Hardened-BYOS Image SLES15-SP6-Hardened-BYOS-Azure Image SLES15-SP6-Hardened-BYOS-EC2 Image SLES15-SP6-Hardened-BYOS-GCE Image SLES15-SP6-SAP Image SLES15-SP6-SAP-Azure Image SLES15-SP6-SAP-EC2 Image SLES15-SP6-SAP-GCE Image SLES15-SP6-SAPCAL Image SLES15-SP6-SAPCAL-Azure Image SLES15-SP6-SAPCAL-EC2 Image SLES15-SP6-SAPCAL-GCE Affected
Container suse/sl-micro/6.0/baremetal-os-container:latest Container suse/sl-micro/6.1/baremetal-os-container:latest Affected
Container suse/sl-micro/6.0/base-os-container:2.1.3-7.95 Container suse/sl-micro/6.1/base-os-container:2.2.1-5.80 Affected
Container suse/sl-micro/6.0/kvm-os-container:2.1.3-6.114 Container suse/sl-micro/6.1/kvm-os-container:2.2.1-5.82 Affected
Container suse/sl-micro/6.0/rt-os-container:2.1.3-7.116 Container suse/sl-micro/6.1/rt-os-container:2.2.1-5.55 Affected

Share

CVE-2025-40129 vulnerability details – vuln.today
Back

This site uses cookies essential for authentication and security. No tracking or analytics cookies are used. Privacy Policy