Integer overflow in Linux kernel - CVE-2026-63984

CSH
CYBERSECURITY HELP
Sign In REGISTER
 
Main Vulnerability Database Vulnerabilities #VU138668

Integer overflow in Linux kernel - CVE-2026-63984

Published: July 20, 2026


Vulnerability identifier: #VU138668
CSH Severity: Medium
CVSS v4: 8.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-63984
CWE-ID: CWE-190
Exploitation vector: Remote access
Exploit availability: No public exploit available

Vulnerability details

The vulnerability allows a remote attacker to corrupt memory in a forwarded packet.

The vulnerability exists due to an integer overflow in ipv6_rpl_srh_decompress() and ipv6_rpl_srh_rcv() when processing a crafted IPv6 RPL source routing header. A remote attacker can send a specially crafted packet to corrupt memory in a forwarded packet.

The issue occurs because the computed hdrlen value can truncate to zero for a large segment count, causing the compressed header to overlap the decompressed routing data.


Affected software

Linux kernel
Red Hat Enterprise Linux for x86_64
Red Hat Enterprise Linux for IBM z Systems
Red Hat Enterprise Linux for ARM 64
Red Hat Enterprise Linux for Power, little endian
Red Hat Enterprise Linux Server - AUS
Red Hat CodeReady Linux Builder for ARM 64 - Extended Update Support
Red Hat CodeReady Linux Builder for IBM z Systems - Extended Update Support
Red Hat CodeReady Linux Builder for Power, little endian - Extended Update Support
Red Hat CodeReady Linux Builder for x86_64 - Extended Update Support
Red Hat Enterprise Linux for ARM 64 - Extended Update Support
Red Hat Enterprise Linux for Power, little endian - Extended Update Support
Red Hat Enterprise Linux for IBM z Systems - Extended Update Support
Red Hat Enterprise Linux for x86_64 - Extended Update Support
Ubuntu
openEuler
Red Hat Enterprise Linux Server for Power LE - Update Services for SAP Solutions
bpftool-debuginfo
kernel-tools-devel
kernel-tools-debuginfo
kernel-tools
kernel-source
kernel-headers
kernel-devel
kernel-debugsource
kernel-debuginfo
bpftool
kernel
perf
perf-debuginfo
python3-perf
python3-perf-debuginfo
kernel (Red Hat package)
kernel-extra-modules
linux-aws (Ubuntu package)
linux (Ubuntu package)
linux-fips (Ubuntu package)
linux-nvidia-tegra (Ubuntu package)
linux-nvidia-tegra-5.15 (Ubuntu package)
linux-ibm-5.15 (Ubuntu package)
linux-aws-5.15 (Ubuntu package)
linux-oracle-5.15 (Ubuntu package)
linux-gcp-5.15 (Ubuntu package)
linux-nvidia (Ubuntu package)
linux-aws-fips (Ubuntu package)
linux-ibm (Ubuntu package)
linux-azure (Ubuntu package)
linux-oracle-7.0 (Ubuntu package)
linux-gcp-7.0 (Ubuntu package)
linux-azure-7.0 (Ubuntu package)
linux-nvidia-bos (Ubuntu package)

How to mitigate CVE-2026-63984

Install security update from vendor's repository.

Linux kernel - update to 7.0 rc3
bpftool-debuginfo - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
kernel-tools-devel - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
kernel-tools-debuginfo - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
kernel-tools - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
kernel-source - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
kernel-headers - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
kernel-devel - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
kernel-debugsource - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
kernel-debuginfo - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
bpftool - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
kernel - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
perf - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
perf-debuginfo - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
python3-perf - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
python3-perf-debuginfo - addressed in versions 5.10.0-329.0.0.230, 6.6.0-145.3.29.160
kernel (Red Hat package) - addressed in versions 5.14.0-427.154.1.el9_4, 5.14.0-687.55.1.el9_8, 6.12.0-55.111.1.el10_0
kernel-extra-modules - update to 6.6.0-145.3.29.160
linux-aws (Ubuntu package) - addressed in versions 5.15.0-194.204~20.04.1, 5.15.0-194.204, 5.15.0-1079.83, 5.15.0-1099.107, 5.15.0-1108.110, 5.15.0-1108.113, 5.15.0-1110.114, 5.15.0-1111.117, 5.15.0-1112.118, 5.15.0-1113.119, 5.15.0-1115.124, 5.15.0-1116.123, 5.15.0-1116.123+fips1, 5.15.0-1116.126+fips1, 5.15.0-1117.127, 5.15.0-1121.130, 5.15.0-1122.131, 5.15.0-1122.131+fips1, 5.15.0.194.159, 5.15.0.1079.82, 5.15.0.1099.98, 5.15.0.1108.104, 5.15.0.1108.112, 5.15.0.1110.107, 5.15.0.1111.110, 5.15.0.1112.111, 5.15.0.1113.109, 5.15.0.1115.119, 5.15.0.1116.106, 5.15.0.1116.112, 5.15.0.1116.119, 5.15.0.1117.114, 5.15.0.1122.106, 5.15.0.1122.120, 6.8.0-1065.68~22.04.1, 6.8.0-1065.68, 7.0.0-1009.9, 7.0.0-1015.15
linux (Ubuntu package) - addressed in versions 5.15.0-194.204, 5.15.0-1111.112, 5.15.0.194.171, 5.15.0.1111.111, 6.8.0-142.142+fips1, 6.8.0-142.142.1~22.04.1, 6.8.0-142.142.1, 6.8.0-1050.54, 6.8.0-1062.65~22.04.1, 6.8.0-1064.72+fips1, 6.8.0-1065.66, 6.8.0-1065.69, 6.8.0-1066.73~22.04.1, 6.8.0-1066.73, 6.8.0-1068.76~22.04.1, 6.8.0-1068.76, 6.8.0-1068.76+fips1, 6.8.0-1069.77~22.04.1, 6.8.0-1069.77, 6.8.0-2054.56, 6.8.1-1060.61~22.04.1, 6.8.1-1060.61
linux-fips (Ubuntu package) - addressed in versions 5.15.0-194.204+fips1, 5.15.0.194.113
linux-nvidia-tegra (Ubuntu package) - addressed in versions 5.15.0-1057.57, 5.15.0-1068.70, 5.15.0.1057.59, 5.15.0.1068.68, 6.8.0-1035.38
linux-nvidia-tegra-5.15 (Ubuntu package) - update to 5.15.0-1068.70~20.04.1
linux-ibm-5.15 (Ubuntu package) - update to 5.15.0-1110.114~20.04.1
linux-aws-5.15 (Ubuntu package) - addressed in versions 5.15.0-1111.117~20.04.1, 5.15.0-1116.123~20.04.1, 5.15.0-1121.130~20.04.1, 5.15.0-1122.131~20.04.1
linux-oracle-5.15 (Ubuntu package) - addressed in versions 5.15.0-1114.120~20.04.1, 5.15.0.1114.120~20.04.1
linux-gcp-5.15 (Ubuntu package) - addressed in versions 5.15.0-1118.128~20.04.1, 5.15.0.1118.128~20.04.1
linux-nvidia (Ubuntu package) - addressed in versions 6.8.0-1063.66~22.04.1, 6.8.0-1063.66, 6.8.0-1063.66.1, 7.0.0-1016.16~24.04.1, 7.0.0-1016.16
linux-aws-fips (Ubuntu package) - update to 6.8.0-1065.68+fips1
linux-ibm (Ubuntu package) - addressed in versions 7.0.0-1008.8, 7.0.0-1010.10
linux-azure (Ubuntu package) - addressed in versions 7.0.0-1009.9, 7.0.0-1010.10
linux-oracle-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-gcp-7.0 (Ubuntu package) - update to 7.0.0-1011.11~24.04.1
linux-azure-7.0 (Ubuntu package) - update to 7.0.0-1014.14~24.04.1
linux-nvidia-bos (Ubuntu package) - update to 7.0.0-2016.16

External References

Related Security Bulletins