CVE-2020-25221

unknown
Published — · Modified —
CVSS v3
CVSS v2
VIR risk

Description

get_gate_page in mm/gup.c in the Linux kernel 5.7.x and 5.8.x before 5.8.7 allows privilege escalation because of incorrect reference counting (caused by gate page mishandling) of the struct page that backs the vsyscall page. The result is a refcount underflow. This can be triggered by any 64-bit process that can use ptrace() or process_vm_readv(), aka CID-9fa2dd946743.

Predictions

Exploit likelihood
20%
Patch ETA

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

vendor Authored 2026-05-27

Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2020-25221

vendor Authored 2026-05-27

Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2020-25221.html

OS impact

OSVersionStatusFixed in
suse slesaffected
debian debianbookwormfixed5.8.7-1
debian debianbullseyefixed5.8.7-1
debian debianforkyfixed5.8.7-1
debian debiansidfixed5.8.7-1
debian debiantrixiefixed5.8.7-1

References

Verify integrity in audit chain (admin only). AS-IS.