Out-of-bounds Read in Linux

CVE-2020-36791

In the Linux kernel, the following vulnerability has been resolved: net_sched: keep alloc_hash updated after hash allocation In commit 599be01ee567 ("net_sched: fix an OOB access in cls_tcindex") I moved cp->hash calculation before the first tcindex_alloc_perfect_hash(), but cp->alloc_hash is left untouched. This difference could lead to another out of bound access. cp->alloc_hash should always be the size allocated, we should update it after this tcindex_alloc_perfect_hash().

Vulnerability class: Buffer Overflow

EPSS: 0.002 (6.6th percentile) — read the EPSS interpretation.

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.

Affected products

  • Linux — versions 73c29d2f6f8ae731b1e09051b69ed3ba2319482b, b974ac51f5834a729de252fc5c1c9de9efd79b45, 6cb448ee493c8a514c9afa0c346f3f5b3227de85
  • Linux Linux_kernel — versions 5.6

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2020-36791?
CVE-2020-36791 is a high-severity vulnerability in Linux, classified under Out-of-bounds Read. CVSS score: 7.8/10. Published 2025-05-07.
How severe is CVE-2020-36791?
High severity. CVSS v3 base score is 7.8 out of 10.