IM
IronMonkey Threat Research

CVE-2026-31630 HIGH

Published: 2026-04-24 | Last Modified: 2026-06-01 | Status: Modified

Description

In the Linux kernel, the following vulnerability has been resolved: rxrpc: proc: size address buffers for %pISpc output The AF_RXRPC procfs helpers format local and remote socket addresses into fixed 50-byte stack buffers with "%pISpc". That is too small for the longest current-tree IPv6-with-port form the formatter can produce. In lib/vsprintf.c, the compressed IPv6 path uses a dotted-quad tail not only for v4mapped addresses, but also for ISATAP addresses via ipv6_addr_is_isatap(). As a result, a case such as [ffff:ffff:ffff:ffff:0:5efe:255.255.255.255]:65535 is possible with the current formatter. That is 50 visible characters, so 51 bytes including the trailing NUL, which does not fit in the existing char[50] buffers used by net/rxrpc/proc.c. Size the buffers from the formatter's maximum textual form and switch the call sites to scnprintf(). Changes since v1: - correct the changelog to cite the actual maximum current-tree case explicitly - frame the proof around the ISATAP formatting path instead of the earlier mapped-v4 example

CVSS Metrics

Base Score: 7.8 (HIGH)

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

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

Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67

Type: Secondary

Exploitability Score: 1.8

Impact Score: 5.9

Weaknesses

Source Type Description
[email protected] Primary
en NVD-CWE-noinfo

Affected Products

Vendor Product Version Update Type
linux linux_kernel * <built-in method update of dict object at 0x7fd2d3b91a80> Operating System
linux linux_kernel * <built-in method update of dict object at 0x7fd2d3b912c0> Operating System
linux linux_kernel 4.9 <built-in method update of dict object at 0x7fd36b89dac0> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7fd348c91e80> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7fd2d3b90380> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7fd2d3b905c0> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7fd2d8259ec0> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7fd340cc4c00> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7fd2d3b91780> Operating System
linux linux_kernel 7.0 <built-in method update of dict object at 0x7fd2d3b91700> 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:4.9:-:*:*:*:*:*:*
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:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*
Yes cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*