CVE-2026-90309 (CVSS 7.8)

Description

In the Linux kernel, the following vulnerability has been resolved: RDMA/erdma: Hold CQ references when processing EQ events EQ handlers look up CQs from dev->cq_xa and invoke CQ completion or error callbacks outside the xarray lock. erdma_destroy_cq() can erase the CQ from the xarray and free its queue buffer and doorbell record while a previously scheduled EQ handler is still using the CQ. Add a CQ refcount and take a reference under the xarray lock with refcount_inc_not_zero(). Remove the CQ from the xarray before dropping the destroy-path reference, then wait for in-flight EQ users before releasing CQ resources.

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CVSS v3.1 Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploit Prediction

0.0017

Probability of exploitation

0.06%

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/05b8ca493dd02319bca93c640b259c2ba51ef321 https://git.kernel.org/stable/c/1fc9c1933959d2776a1ce7bf424251b8b5b586cd https://git.kernel.org/stable/c/4545f355654d044d35a31cd01cc46f491a8a7c36 https://git.kernel.org/stable/c/610ef81797bb4f709e8675c1d8d093bb9ccdcbd8 https://git.kernel.org/stable/c/98df2aee1459ee1c62c70cbe9b370d2a532aea36 https://git.kernel.org/stable/c/c0a83f29a24c7e7f8516630848ef6db4c174deed

Frequently Asked Questions

What is CVE-2026-90309? +

In the Linux kernel, the following vulnerability has been resolved: RDMA/erdma: Hold CQ references when processing EQ events EQ handlers look up CQs from dev->cq_xa and invoke CQ completion or error callbacks outside the xarray lock. erdma_destroy_cq() can erase the CQ from the xarray and free its queue buffer and doorbell record while a previously scheduled EQ handler is still using the CQ. Add a CQ refcount and take a reference under the xarray lock with refcount_inc_not_zero(). Remove the CQ from the xarray before dropping the destroy-path reference, then wait for in-flight EQ users before releasing CQ resources. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2026-90309? +

CVE-2026-90309 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching. The EPSS score is 0.0017, placing it in the 0th percentile for exploitation probability.

How do I check if I'm vulnerable to CVE-2026-90309? +

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.

CVE-2026-90309