CVE-2020-25221
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.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.67%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
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.
- CVSS 3.1
- 7.8 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.67% probability · 50th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-672
- Affected
- linux/linux kernel · netapp/cloud backup · netapp/solidfire\, enterprise sds \& hci storage node · netapp/solidfire \& hci management node · netapp/hci compute node · netapp/solidfire baseboard management controller
- Source
- cve@mitre.org
References
- http://www.openwall.com/lists/oss-security/2020/09/10/4Mailing List, Third Party Advisory
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.8.7Release Notes, Vendor Advisory
- https://git.kernel.org/linus/8891adc61dce2a8a41fc0c23262b681c3ec4b73aIssue Tracking, Patch, Vendor Advisory
- https://git.kernel.org/linus/9fa2dd946743ae6f30dc4830da19147bf100a7f2Issue Tracking, Patch, Vendor Advisory
- https://security.netapp.com/advisory/ntap-20201001-0003/Third Party Advisory
- https://www.openwall.com/lists/oss-security/2020/09/08/4Mailing List, Patch, Third Party Advisory
- http://www.openwall.com/lists/oss-security/2020/09/10/4Mailing List, Third Party Advisory
- https://cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.8.7Release Notes, Vendor Advisory
- https://git.kernel.org/linus/8891adc61dce2a8a41fc0c23262b681c3ec4b73aIssue Tracking, Patch, Vendor Advisory
- https://git.kernel.org/linus/9fa2dd946743ae6f30dc4830da19147bf100a7f2Issue Tracking, Patch, Vendor Advisory
- https://security.netapp.com/advisory/ntap-20201001-0003/Third Party Advisory
- https://www.openwall.com/lists/oss-security/2020/09/08/4Mailing List, Patch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.