Use After Free in Linux
CVE-2026-52971
In the Linux kernel, the following vulnerability has been resolved: net: ena: PHC: Fix potential use-after-free in get_timestamp Move the phc->active check and resp pointer assignment to after acquiring the spinlock. Previously, phc->active was checked without holding the lock, and resp was cached from ena_dev->phc.virt_addr before the lock was acquired. If ena_com_phc_destroy() runs between the lockless active check and the lock acquisition, it sets active=false, releases the lock, frees the DMA memory, and sets virt_addr=NULL. The get_timestamp path would then read a NULL virt_addr and dereference it. With both the active check and the pointer read under the lock, destroy cannot free the memory while get_timestamp is using it.
Vulnerability class: Use-After-Free
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.001 (2.3th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 2nd percentile — 2.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.001 · newest: 0.001 · change: 0.000
Affected products
- Linux — versions e0ea34158ee8c4f7536cd781010339ff28c0d24c, 6.17, 0
- Linux Kernel — versions 7.1
Weakness classification (CWE)
References
Frequently asked questions
- What is CVE-2026-52971?
- CVE-2026-52971 is a high-severity vulnerability in Linux, classified under Use After Free. CVSS score: 7.8/10. Published 2026-06-24.
- How severe is CVE-2026-52971?
- High severity. CVSS v3 base score is 7.8 out of 10.