← Vulnerability feed

Vulnerability record · CVE-2026-31474 · published 22 April 2026

CVE-2026-31474: Linux kernel use after free vulnerability

Linux · Linux Kernel

In the Linux kernel, the following vulnerability has been resolved: can: isotp: fix tx.buf use-after-free in isotp_sendmsg() isotp_sendmsg() uses only cmpxchg() on so->tx.state to serialize access to so->tx.buf. isotp_release() waits for ISOTP_IDLE via wait_event_interruptible() and then calls kfree(so->tx.buf). If a signal interrupts the wait_event_interruptible() inside close() while tx.state is ISOTP_SENDING, the loop exits early and release proceeds to force ISOTP_SHUTDOWN and continues to kfree(so->tx.buf) while sendmsg may still be reading so->tx.buf for the final CAN frame in isotp_fill_dataframe(). The so->tx.buf can be allocated once when the standard tx.buf length needs to be extended. Move the kfree() of this potentially extended tx.buf to sk_destruct time when either isotp_sendmsg() and isotp_release() are done.

7.8 CVSS 3.1 High EPSS 0.14% · top 97.1% CWE-416 · Use after freeCWE-364 · CWE-364
7.8CVSS 3.1 base score
0.14%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
11References
15 Jul 2026Last modified by NVD

Description

In the Linux kernel, the following vulnerability has been resolved: can: isotp: fix tx.buf use-after-free in isotp_sendmsg() isotp_sendmsg() uses only cmpxchg() on so->tx.state to serialize access to so->tx.buf. isotp_release() waits for ISOTP_IDLE via wait_event_interruptible() and then calls kfree(so->tx.buf). If a signal interrupts the wait_event_interruptible() inside close() while tx.state is ISOTP_SENDING, the loop exits early and release proceeds to force ISOTP_SHUTDOWN and continues to kfree(so->tx.buf) while sendmsg may still be reading so->tx.buf for the final CAN frame in isotp_fill_dataframe(). The so->tx.buf can be allocated once when the standard tx.buf length needs to be extended. Move the kfree() of this potentially extended tx.buf to sk_destruct time when either isotp_sendmsg() and isotp_release() are done.

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

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://git.kernel.org/stable/c/2e62e7051eca75a7f2e3d52d62ec10d7d7aa358c Patch
https://git.kernel.org/stable/c/424e95d62110cdbc8fd12b40918f37e408e35a92 Patch
https://git.kernel.org/stable/c/9649d051e54413049c009638ec1dc23962c884a4 Patch
https://git.kernel.org/stable/c/cb3d6efa78460e6d50bf68806d0db66265709f64 Patch
https://git.kernel.org/stable/c/eec8a1b18a79600bd4419079dc0026c1db72a830 Patch
https://access.redhat.com/errata/RHSA-2026:27288
https://access.redhat.com/errata/RHSA-2026:27731
https://access.redhat.com/errata/RHSA-2026:27789
https://access.redhat.com/security/cve/CVE-2026-31474
https://bugzilla.redhat.com/show_bug.cgi?id=2460646
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31474.json

Track CVE-2026-31474 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2025-39682Linux kernel TLS zero-length record handling flaw on rx_listThe Linux kernel TLS receive path mishandles zero-length records that arrive from the rx_list, breaking the assumption that a record type change cann…KEVEPSS 2.9%analysed8.8CVE-2026-53266Linux kernel ebtables SNAT out-of-bounds write in ARP rewriteThe ebtables SNAT target rewrites the ARP sender hardware address via skb_store_bits() without first making that range writable. When the ARP SHA byt…KEVEPSS 0.65%analysed8.8CVE-2023-3079Google Chrome V8 type confusion enables heap corruptionCVE-2023-3079 is a type confusion flaw in the V8 JavaScript engine in Google Chrome before 114.0.5735.110. A crafted HTML page can trigger the confus…KEVEPSS 32%analysed8.8CVE-2013-6282Linux kernel ARM get_user/put_user missing address validationThe get_user and put_user API functions in the Linux kernel before 3.5.5 on v6k and v7 ARM platforms fail to validate certain addresses, allowing cra…KEVEPSS 40%analysed8.4CVE-2022-0185Linux Kernel Filesystem Context Heap Buffer OverflowThe legacy_parse_param function in the Linux kernel's Filesystem Context functionality fails to properly verify supplied parameter lengths, causing a…KEVEPSS 25%analysed8.4CVE-2013-2094Linux Kernel perf_swevent_init Integer Type Flaw Enables Local Privilege EscalationThe perf_swevent_init function in kernel/events/core.c in the Linux kernel before 3.8.9 uses an incorrect integer data type, allowing a local user to…KEVEPSS 48%analysed7.8CVE-2026-53362Linux kernel IPv6 UDP paged allocation out-of-bounds write__ip6_append_data() in the Linux kernel mis-accounts fraggap on the paged-allocation path, leaving the linear skb area undersized while pagedlen is o…KEVEPSS 0.71%analysed7.8CVE-2026-31431Linux kernel algif_aead in-place crypto operation flawThe Linux kernel's algif_aead AF_ALG AEAD interface operated in-place on buffers that come from different mappings, a flaw the fix resolves by revert…KEVEPSS 3.4%analysed

Source: NIST National Vulnerability Database (record CVE-2026-31474), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.