How to Fix CVE-2026-43010: bpf: Reject sleepable kprobe_multi programs at attach time in Linux
By Sai Kiran Pandrala
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Last verified: 2026-05-25
CVE-2026-43010 is a bpf: reject sleepable kprobe_multi programs at attach time in Linux Linux. Fix it by upgrading to 6.18.22, 6.19.12, 7.0.
| Severity | Not verified - see official advisory |
|---|---|
| Actively exploited? | Not currently in the CISA KEV catalog |
| Affected | Linux 0dcac272540613d41c05e89679e4ddb978b612f1 up to (excluding) dc9a060d76c12b23c5f378ee115d5e5d03d8bbf3; Linux 0dcac272540613d41c05e89679e4ddb978b612f1 up to (excluding) f952157e695fd434bdc05af63a703bb082a78717; Linux 0dcac272540613d41c05e89679e4ddb978b612f1 up to (excluding) eb7024bfcc5f68ed11ed9dd4891a3073c15f04a8; Linux 5.18 |
| Fixed in | 6.18.22, 6.19.12, 7.0 |
| Type (CWE) | Not verified |
What is CVE-2026-43010?
CVE-2026-43010 is a bpf: reject sleepable kprobe_multi programs at attach time flaw in Linux Linux. The vendor has not published a verified CVSS metric at the time of writing. It is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
From the source record: In the Linux kernel, the following vulnerability has been resolved:
bpf: Reject sleepable kprobe_multi programs at attach time
kprobe.multi programs run in atomic/RCU context and cannot sleep.
However, bpf_kprobe_multi_link_attach() did not validate whether the
program being attached had the sleepable flag set, allowing sleepable
helpers such as bpf_copy_from_user() to be invoked from a non-sleepable
context.
This causes a "sleeping function called from invalid context" splat:
BUG: sleeping function called from invalid context at ./include/linux/uaccess.h:169
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1787, name: sudo
preempt_count: 1, expected: 0
RCU nest depth: 2, expected: 0
Fix this by rejecting sleepable programs early in
bpf_kprobe_multi_link_attach(), before any further processing.
Why it matters in practice: The blast radius depends on how the affected service is exposed. An internet-facing instance with no compensating controls is the highest-risk configuration.
Am I affected?
You are affected if your installation of Linux matches a version listed in the Affected row above.
# Debian/Ubuntu
dpkg -s linux | grep Version
# RHEL/Rocky
rpm -q linux
How to fix CVE-2026-43010
Apply the vendor patch. Target the build named in the Fixed in row above (6.18.22, 6.19.12, 7.0). The runnable command set below covers the most common deployment patterns for Linux.
Ubuntu / Debian
sudo apt-get update
sudo apt-get install --only-upgrade linux
dpkg -s linux | grep Version
RHEL / CentOS / Rocky
sudo dnf upgrade linux -y
rpm -q linux
After applying the patch
- Restart the service or device so the patched binary loads.
- Confirm the running version matches the Fixed in row using the verification command below.
- Rotate credentials and API keys that the affected service could access if the asset was exposed during the disclosure window.
If you can't patch immediately
Until the patch lands, narrow the attack surface with these runnable controls.
Restrict network exposure
Block public access to the affected service at the perimeter. Allow only trusted source IPs.
# Linux iptables: only allow trusted admin subnet
sudo iptables -A INPUT -p tcp --dport 443 -s 10.10.10.0/24 -j ACCEPT
sudo iptables -A INPUT -p tcp --dport 443 -j DROP
sudo iptables-save | sudo tee /etc/iptables/rules.v4
# Windows firewall: only allow trusted admin subnet on management port
New-NetFirewallRule -DisplayName "Restrict-Mgmt-Allow" -Direction Inbound -Action Allow `
-RemoteAddress 10.10.10.0/24 -Protocol TCP -LocalPort 443
New-NetFirewallRule -DisplayName "Restrict-Mgmt-Deny" -Direction Inbound -Action Block `
-Protocol TCP -LocalPort 443
Mitigations are temporary. Apply the vendor patch as soon as a maintenance window opens.
How to verify the fix worked
Confirm the patched build is the one actually running.
# Debian/Ubuntu
dpkg -s linux | grep Version
# RHEL/Rocky
rpm -q linux
Expected: a version at or above 6.18.22, 6.19.12, 7.0.
Also worth doing: pull recent log windows for indicators of compromise listed in the vendor advisory, and re-run an authenticated vulnerability scan with up-to-date signatures.
Frequently asked questions
Is CVE-2026-43010 being exploited in the wild?
As of 2026-05-25, CVE-2026-43010 is not listed in the CISA Known Exploited Vulnerabilities catalog. Watch the catalog and patch on a normal cadence; KEV status can change as exploitation evidence emerges.
What is the CVSS score for CVE-2026-43010?
A verified CVSS score is not listed in the public record for CVE-2026-43010. Check the vendor advisory and the NVD page for an updated metric.
What version fixes this?
Upgrade to 6.18.22, 6.19.12, 7.0.
Will a WAF or IDS rule alone close this?
No. Network filters cut down opportunistic scans but they do not remove the flaw. The vendor patch is the only durable fix.
References
- Official vendor advisory: https://git.kernel.org/stable/c/dc9a060d76c12b23c5f378ee115d5e5d03d8bbf3
- NVD entry: https://nvd.nist.gov/vuln/detail/CVE-2026-43010
- CISA KEV catalog: https://www.cisa.gov/known-exploited-vulnerabilities-catalog
- Additional reference: https://git.kernel.org/stable/c/f952157e695fd434bdc05af63a703bb082a78717
- Additional reference: https://git.kernel.org/stable/c/eb7024bfcc5f68ed11ed9dd4891a3073c15f04a8
*Assembled from the official vendor advisory, the NVD record, and the CISA KEV listing on 2026-05-25. Always confirm against the vendor advisory before applying changes in production.*