CVE-2026-100080

Description

In the Linux kernel, the following vulnerability has been resolved: xen-netback: Fix UAF when reading statistics data The network statistic data in the driver is protected by RCU. Unfortunately when tearing down the queues after an error during connecting to the frontend (e.g. due to illegal Xenstore data filled in by the guest), the statistic data is being freed without synchronizing the RCU state. In case the data is being read via sysfs in this phase, access to already freed memory or memory being in new use is possible. Fix that by calling synchronize_net() before freeing the queue data. This is XSA-526 / CVE-2026-100080

Is your site exposed to CVE-2026-100080?

Run a free security scan — no signup, results in seconds.

EPSS — Exploit Prediction

0.0027

Probability of exploitation

0.19%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/36f858f228e3f955b9336af7f94634747c221518 https://git.kernel.org/stable/c/37d5a73170579b30e67cc8b19ec69715eea3a6b6 https://git.kernel.org/stable/c/4223b33be49ee09acb6f1d26beb4a36dd3b8d63a https://git.kernel.org/stable/c/4867687b6ad28ab84bc0811d8f8f9972e769da02 https://git.kernel.org/stable/c/6cd611d2abdd8623a554e14145f82c1cb4e4467a https://git.kernel.org/stable/c/89e534265b62c94749639350200b10370564bb3a https://git.kernel.org/stable/c/ab9cdf1291be551da999510b30216a2886074d7a http://www.openwall.com/lists/oss-security/2026/11/06/9 http://xenbits.xen.org/xsa/advisory-526.html

Frequently Asked Questions

What is CVE-2026-100080? +

In the Linux kernel, the following vulnerability has been resolved: xen-netback: Fix UAF when reading statistics data The network statistic data in the driver is protected by RCU. Unfortunately when tearing down the queues after an error during connecting to the frontend (e.g. due to illegal Xenstore data filled in by the guest), the statistic data is being freed without synchronizing the RCU state. In case the data is being read via sysfs in this phase, access to already freed memory or memory being in new use is possible. Fix that by calling synchronize_net() before freeing the queue data. This is XSA-526 / CVE-2026-100080

How do I check if I'm vulnerable to CVE-2026-100080? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.