CVE-2026-72427
bpf: Fix effective prog array index with BPF_F_PREORDER
Description
In the Linux kernel, the following vulnerability has been resolved: bpf: Fix effective prog array index with BPF_F_PREORDER replace_effective_prog() and purge_effective_progs() located the slot in the effective array by walking the program hlist and counting entries linearly. That count does not match the array layout: compute_effective_ progs() places BPF_F_PREORDER programs at the front (ancestor cgroup first, attach order within a cgroup) and the rest after them (descendant cgroup first). So when a preorder program is present, the linear hlist position no longer equals the program's index in the effective array. For replace_effective_prog() (bpf_link_update()) this overwrote the wrong slot, corrupting the effective order. For purge_effective_progs(), it could dummy out a slot belonging to a different program and leave the detached program in the array while bpf_prog_put() drops its reference, i.e. a use-after-free. Fix both by replaying compute_effective_progs()'s placement (including the per-cgroup preorder reversal) in a shared effective_prog_pos() helper. Identify the entry by its struct bpf_prog_list pointer rather than by (prog, link) value, so the lookup resolves to exactly the attachment the syscall selected even when the same bpf_prog is attached to several cgroups in the hierarchy.
INFO
Published Date :
Aug. 15, 2026, 6:22 a.m.
Last Modified :
Aug. 17, 2026, 6:19 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Update the Linux kernel to the latest version.
- Replay program placement logic using effective_prog_pos().
- Identify entries by struct bpf_prog_list pointer.
- Review program linking and attachment logic.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-72427.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-72427 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-72427
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-72427 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-72427 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 17, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Changed Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'bc8023ef3b11410682e5d4990e05e5bc2d3e1c94', 'lessThan': '525e408c27ae714e538b8c608c3a974df3ab6c92', 'versionType': 'git'}, {'status': 'affected', 'version': '555c0b713ca83968d3c843cb15485b9ba3367b1b', 'lessThan': '41b4320b84fdafe1ab586b06453d30d50415db59', 'versionType': 'git'}, {'status': 'affected', 'version': '4b82b181a26cff8bf7adc3a85a88d121d92edeaf', 'lessThan': '9697db03e010391c55ae75192cbdf30c5a72c114', 'versionType': 'git'}, {'status': 'affected', 'version': '4b82b181a26cff8bf7adc3a85a88d121d92edeaf', 'lessThan': 'b584f107ab90222bd825dcb4c5977326ff684109', 'versionType': 'git'}, {'status': 'affected', 'version': '4b82b181a26cff8bf7adc3a85a88d121d92edeaf', 'lessThan': 'f08aaee3152d0dfc578b3f2586932d82062701dd', 'versionType': 'git'}, {'status': 'affected', 'version': '4707ad649cf662add3058bff47430817811b048d', 'versionType': 'git'}, {'status': 'affected', 'version': '6.6.93', 'lessThan': '6.6.145', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.12.31', 'lessThan': '6.12.97', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.14.9', 'lessThan': '6.15', 'versionType': 'semver'}], 'programFiles': ['kernel/bpf/cgroup.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.15'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.15', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/bpf/cgroup.c'], 'defaultStatus': 'affected'}] [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'bc8023ef3b11410682e5d4990e05e5bc2d3e1c94', 'lessThan': '525e408c27ae714e538b8c608c3a974df3ab6c92', 'versionType': 'git'}, {'status': 'affected', 'version': '555c0b713ca83968d3c843cb15485b9ba3367b1b', 'lessThan': '41b4320b84fdafe1ab586b06453d30d50415db59', 'versionType': 'git'}, {'status': 'affected', 'version': '4b82b181a26cff8bf7adc3a85a88d121d92edeaf', 'lessThan': '9697db03e010391c55ae75192cbdf30c5a72c114', 'versionType': 'git'}, {'status': 'affected', 'version': '4b82b181a26cff8bf7adc3a85a88d121d92edeaf', 'lessThan': 'b584f107ab90222bd825dcb4c5977326ff684109', 'versionType': 'git'}, {'status': 'affected', 'version': '4b82b181a26cff8bf7adc3a85a88d121d92edeaf', 'lessThan': 'f08aaee3152d0dfc578b3f2586932d82062701dd', 'versionType': 'git'}, {'status': 'affected', 'version': '4707ad649cf662add3058bff47430817811b048d', 'versionType': 'git'}, {'status': 'affected', 'version': '6.6.93', 'lessThan': '6.6.145', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.12.31', 'lessThan': '6.12.97', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.14.9', 'lessThan': '6.15', 'versionType': 'semver'}], 'programFiles': ['kernel/bpf/cgroup.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.15'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.15', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/bpf/cgroup.c'], 'defaultStatus': 'affected'}] -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 15, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'bc8023ef3b11410682e5d4990e05e5bc2d3e1c94', 'lessThan': '525e408c27ae714e538b8c608c3a974df3ab6c92', 'versionType': 'git'}, {'status': 'affected', 'version': '555c0b713ca83968d3c843cb15485b9ba3367b1b', 'lessThan': '41b4320b84fdafe1ab586b06453d30d50415db59', 'versionType': 'git'}, {'status': 'affected', 'version': '4b82b181a26cff8bf7adc3a85a88d121d92edeaf', 'lessThan': '9697db03e010391c55ae75192cbdf30c5a72c114', 'versionType': 'git'}, {'status': 'affected', 'version': '4b82b181a26cff8bf7adc3a85a88d121d92edeaf', 'lessThan': 'b584f107ab90222bd825dcb4c5977326ff684109', 'versionType': 'git'}, {'status': 'affected', 'version': '4b82b181a26cff8bf7adc3a85a88d121d92edeaf', 'lessThan': 'f08aaee3152d0dfc578b3f2586932d82062701dd', 'versionType': 'git'}, {'status': 'affected', 'version': '4707ad649cf662add3058bff47430817811b048d', 'versionType': 'git'}, {'status': 'affected', 'version': '6.6.93', 'lessThan': '6.6.145', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.12.31', 'lessThan': '6.12.97', 'versionType': 'semver'}, {'status': 'affected', 'version': '6.14.9', 'lessThan': '6.15', 'versionType': 'semver'}], 'programFiles': ['kernel/bpf/cgroup.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.15'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.15', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.6.145', 'versionType': 'semver', 'lessThanOrEqual': '6.6.*'}, {'status': 'unaffected', 'version': '6.12.97', 'versionType': 'semver', 'lessThanOrEqual': '6.12.*'}, {'status': 'unaffected', 'version': '6.18.40', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.5', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2-rc1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['kernel/bpf/cgroup.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: bpf: Fix effective prog array index with BPF_F_PREORDER replace_effective_prog() and purge_effective_progs() located the slot in the effective array by walking the program hlist and counting entries linearly. That count does not match the array layout: compute_effective_ progs() places BPF_F_PREORDER programs at the front (ancestor cgroup first, attach order within a cgroup) and the rest after them (descendant cgroup first). So when a preorder program is present, the linear hlist position no longer equals the program's index in the effective array. For replace_effective_prog() (bpf_link_update()) this overwrote the wrong slot, corrupting the effective order. For purge_effective_progs(), it could dummy out a slot belonging to a different program and leave the detached program in the array while bpf_prog_put() drops its reference, i.e. a use-after-free. Fix both by replaying compute_effective_progs()'s placement (including the per-cgroup preorder reversal) in a shared effective_prog_pos() helper. Identify the entry by its struct bpf_prog_list pointer rather than by (prog, link) value, so the lookup resolves to exactly the attachment the syscall selected even when the same bpf_prog is attached to several cgroups in the hierarchy. Added Reference https://git.kernel.org/stable/c/41b4320b84fdafe1ab586b06453d30d50415db59 Added Reference https://git.kernel.org/stable/c/525e408c27ae714e538b8c608c3a974df3ab6c92 Added Reference https://git.kernel.org/stable/c/9697db03e010391c55ae75192cbdf30c5a72c114 Added Reference https://git.kernel.org/stable/c/b584f107ab90222bd825dcb4c5977326ff684109 Added Reference https://git.kernel.org/stable/c/f08aaee3152d0dfc578b3f2586932d82062701dd