IM
IronMonkey Threat Research

CVE-2026-31428 MEDIUM

Published: 2026-04-13 | Last Modified: 2026-07-14 | Status: Modified

Description

In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_log: fix uninitialized padding leak in NFULA_PAYLOAD __build_packet_message() manually constructs the NFULA_PAYLOAD netlink attribute using skb_put() and skb_copy_bits(), bypassing the standard nla_reserve()/nla_put() helpers. While nla_total_size(data_len) bytes are allocated (including NLA alignment padding), only data_len bytes of actual packet data are copied. The trailing nla_padlen(data_len) bytes (1-3 when data_len is not 4-byte aligned) are never initialized, leaking stale heap contents to userspace via the NFLOG netlink socket. Replace the manual attribute construction with nla_reserve(), which handles the tailroom check, header setup, and padding zeroing via __nla_reserve(). The subsequent skb_copy_bits() fills in the payload data on top of the properly initialized attribute.

CVSS Metrics

Base Score: 5.5 (MEDIUM)

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Attack VectorLOCAL
Attack ComplexityLOW
Privileges RequiredLOW
User InteractionNONE
ScopeUNCHANGED
Confidentiality ImpactNONE
Integrity ImpactNONE
Availability ImpactHIGH

Source: [email protected]

Type: Primary

Exploitability Score: 1.8

Impact Score: 3.6

Weaknesses

Source Type Description
[email protected] Primary
en CWE-908

Affected Products

Vendor Product Version Update Type
linux linux_kernel * <built-in method update of dict object at 0x702bcc124780> Operating System
linux linux_kernel * <built-in method update of dict object at 0x702bdc59f200> Operating System
linux linux_kernel * <built-in method update of dict object at 0x702bcc1268c0> Operating System
linux linux_kernel * <built-in method update of dict object at 0x702bdc373280> Operating System
linux linux_kernel * <built-in method update of dict object at 0x702bcc125480> Operating System
linux linux_kernel * <built-in method update of dict object at 0x702bcc126680> Operating System
linux linux_kernel * <built-in method update of dict object at 0x702bdc59dd80> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x702bfc369340> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x702bdc59e580> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x702bcc124640> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x702bfc58f8c0> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x702bdc59d740> Operating System

Affected Configurations

Operator: OR

Vulnerable CPE
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*

References

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