CVE-2025-38181: calipso: Fix null-ptr-deref in calipso_req_{set,del}attr().

Published Jul 4, 2025
·
Updated

calipso: Fix null-ptr-deref in calipsoreq{set,del}attr().

Affected Software

13 affected componentsFixes available
Linux Foundation Linux Kernel
Linux Linux kernel>=4.8<5.4.295
Linux Linux kernel>=5.5<5.10.239
Linux Linux kernel>=5.11<5.15.186
Linux Linux kernel>=5.16<6.1.142
Linux Linux kernel>=6.2<6.6.95
Linux Linux kernel>=6.7<6.12.35
Linux Linux kernel>=6.13<6.15.4
Linux Linux kernel=6.16-rc1
Linux Linux kernel=6.16-rc2
Debian Debian Linux=11.0
Microsoft azl3 kernel 6.6.92.2-2
Microsoft azl3 kernel 6.6.96.1-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Patch 3b24d854cb35
  2. Configuration

    Modify calipso_req_setattr() and calipso_req_delattr() to return an error to prevent the null-ptr-deref in calipso_req_{set,del}attr() (net/ipv6/calipso.c:1204).

    Linux kernel (CALIPSO / netlabel) calipso_req_setattr() and calipso_req_delattr() behavior = Return an error
  3. Compensating control

    Rely on SYN Cookie behavior so that request_sock->rsk_listener may be NULL without triggering the calipso_req_{set,del}attr() null-ptr-deref (the crash occurs when SYN Cookie is returned and reqsk->rsk_listener could be NULL).

Event History

Jul 4, 2025
CVE Published
via MITRE·01:37 PM
Data Sourced
via MITRE·01:37 PM
DescriptionSeverity
Data Sourced
via NVD·02:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Aug 7, 2025
Data Sourced
via Microsoft·07:00 AM
DescriptionSeverityWeakness
Data Sourced
via Microsoft·07:00 AM
Affected Software
Updated
via Microsoft·07:00 AM
SeverityAffected Software
Updated
via Microsoft·07:00 AM
DescriptionSeverity

Frequently Asked Questions

1

What is the severity of CVE-2025-38181?

CVE-2025-38181 has been classified with a severity level that indicates a potential impact on system stability due to a null pointer dereference.

2

How do I fix CVE-2025-38181?

To fix CVE-2025-38181, update your Linux kernel to the latest patched version that addresses the null pointer dereference in calipso_req_{set,del}attr().

3

What systems are affected by CVE-2025-38181?

CVE-2025-38181 affects various versions of the Linux kernel used in multiple Linux distributions.

4

What causes the vulnerability in CVE-2025-38181?

CVE-2025-38181 is caused by a null pointer dereference occurring in the allocation of a CALIPSO option when processing socket operations.

5

Is there a mitigation for CVE-2025-38181 if I cannot update?

If immediate updating is not feasible, review your server configurations to avoid socket operations that may trigger the null pointer dereference in applications using CALIPSO.

Contact

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