CVE-2026-98626 json
bpf: Restrict CO-RE poisoning to relocatable instructions
published 24d ago modified 24d ago also EUVD-2026-103540
- cvss
- —
- not scored
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 11%
- public exploits
- 0
- none known
Summary
In the Linux kernel, the following vulnerability has been resolved:
bpf: Restrict CO-RE poisoning to relocatable instructions
CO-RE relocation records can name any instruction offset. When a relocation cannot be resolved, bpf_core_patch_insn() currently poisons its target before checking whether that instruction is a valid relocation target. Malformed metadata can therefore replace jumps, calls, exits, register-source arithmetic, or non-immediate loads instead of failing at the relocation step.
Handle poisoning only after the instruction has passed the same class and operand-form checks used for a resolved relocation. Route invalid forms through the existing diagnostic and return a hard error. Keep poisoning supported instructions, including both halves of a plain ldimm64, so an unresolved relocation in dead code remains valid.
Extend bpf_core_poison_insn() to poison both halves of ldimm64, and return its status directly from each validated instruction case. This avoids routing the success path through a common label and leaves the helper free to report errors.
The shared relocation code applies this restriction to both libbpf and in-kernel CO-RE.
Patch / fix
- Linux Linux 7.3
- linux Debian 12 6.1.190-1
- linux Debian 13 6.12.113-1
- linux Debian 14 7.2.9-1
- linux-6.12 Debian 12 6.12.113-1~deb12u1
debian advisories DEBIAN-CVE-2026-98626
- linux Ubuntu 22.04 LTS 5.15.0-202.212
- linux Ubuntu 24.04 LTS 6.8.0-149.149
- linux Ubuntu 26.04 LTS 7.0.0-42.42
- linux-aws Ubuntu 22.04 LTS 5.15.0-1119.126
- linux-aws Ubuntu 24.04 LTS 6.8.0-1069.74
- linux-aws Ubuntu 26.04 LTS 7.0.0-1016.17
- linux-gcp Ubuntu 22.04 LTS 5.15.0-1120.130
- linux-gcp Ubuntu 24.04 LTS 6.8.0-1073.81
ubuntu advisories UBUNTU-CVE-2026-98626
Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0
- kernel Azure Linux 3.0 6.6.159.1-1
azure linux advisories AZL-108947
Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT
- git.kernel.org/stable/c/a8c47e62d9aea2d47a09e06c1682c59c21b92449 commit
- git.kernel.org/stable/c/d3219c229d16900cef936adad28633c98946e432 commit
- git.kernel.org/stable/c/a0b79cdfcf34b53c85bac2d3cf022fc1342eeca0 commit
- git.kernel.org/stable/c/f2a24101e89dd0804e717da7c1bd6af513698aa2 commit
- git.kernel.org/stable/c/2d7d04357c41aa49a5ac658fcc207439f2ad6456 commit
- git.kernel.org/stable/c/8e4cbcca1e0a2fc5e6c8edb68e0cf5f2587f9319 commit
- git.kernel.org/stable/c/394ae398337c5f87e567f6cd63b937fc2b2f6ddc commit
Is CVE-2026-98626 in your stack? Fencer shows which of your repositories are affected as soon as an advisory lands, and opens the fix as a pull request.
Check with FencerVendor advisories
What the vendors themselves say about their products: affected, fixed or not affected, and what to do.
red hat product security vex CVE-2026-98626 updated cvss 4.4
kernel: bpf: Restrict CO-RE poisoning to relocatable instructions
-
Red Hat Enterprise Linux 6 perf, kernel, python-perf, kernel-kdump, kernel-firmware, kernel-bootwrapper, +1 more Red Hat Enterprise Linux 7 perf, kernel, bpftool, kernel-rt, python-perf, kernel-kdump, +8 more Red Hat Enterprise Linux 8 perf, kernel, bpftool, kernel-rt, kernel-core, kernel-tools, +29 more Red Hat Enterprise Linux 9 rv, perf, rtla, kernel, bpftool, libperf, +83 more Red Hat Enterprise Linux 10 kernel Red Hat OpenShift Container Platform 4 openshift/ose-rhel-coreos-8, openshift/ose-rhel-coreos-9not affected: vulnerable code not present
+1 more productsfewer
Red Hat OpenShift Container Platform 5 openshift/ose-rhel-coreos-9
Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf
Exploit prediction
0.21% chance of exploitation in the next 30 days, higher than 11% of all scored CVEs (FIRST EPSS, 2026-11-11).
Affected products
- Linux Linux
Classification
- Technology feeds
References
- git.kernel.org /stable/c/a8c47e62d9aea2d47a09e06c1682c59c21b92449
- git.kernel.org /stable/c/d3219c229d16900cef936adad28633c98946e432
- git.kernel.org /stable/c/a0b79cdfcf34b53c85bac2d3cf022fc1342eeca0
- git.kernel.org /stable/c/f2a24101e89dd0804e717da7c1bd6af513698aa2
- git.kernel.org /stable/c/2d7d04357c41aa49a5ac658fcc207439f2ad6456
- git.kernel.org /stable/c/8e4cbcca1e0a2fc5e6c8edb68e0cf5f2587f9319
- git.kernel.org /stable/c/394ae398337c5f87e567f6cd63b937fc2b2f6ddc
Sources
- CVE List CVE-2026-98626
- NVD CVE-2026-98626
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