CVE-2020-12771

Exp

An issue was discovered in the Linux kernel through 5.6.11. btree_gc_coalesce in drivers/md/bcache/btree.c has a deadlock if a coalescing operation fails.

Published: 2020-05-09 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2020-12771 is rated Exploit Available (51.4/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.52%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2020-12771

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2020-12771

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.05% 0.52% +0.47%
2 2026-02-21 0.06% 0.05% -0.01%
3 2025-11-21 — 0.06% —

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2020-12771

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.5 3.1 MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:L)
They already need access on the box, or another person has to do something wrong; it’s not a remote drive-by.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 1.8 3.6 [email protected]
4.9 2.0 MEDIUM
AV:L/AC:L/Au:N/C:N/I:N/A:C Click to expand
Access vector (AV:L)
Requires local access to the target system.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:C)
Complete availability impact.
 3.9 6.9 [email protected]

Weakness enumeration for CVE-2020-12771

OS Trackers for CVE-2020-12771

vendor priority summary link
debian not yet assigned CVE-2020-12771 not yet assigned priority: Debian including 1 source packages (linux), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2020-12771
redhat low — https://access.redhat.com/security/cve/CVE-2020-12771
suse medium CVE-2020-12771 severity moderate: SUSE including 607 source package names (amazon/suse-sles-15-sp1-chost-byos-v20210304-hvm-ssd-x86_64, amazon/suse-sles-15-sp1-chost-byos-v20220127-hvm-ssd-x86_64, …), 1040 product×package rows across 126 product lines (HPE Helion OpenStack 8, Image SLES12-SP5-Azure-BYOS, … (126 product lines)): Fixed 791, Known Affected 157, Known Not Affected 92. https://www.suse.com/security/cve/CVE-2020-12771/
ubuntu low CVE-2020-12771 low priority: Ubuntu including 115 source packages (linux, linux-aws, …), 1225 status rows across 13 suites (bionic, eoan, focal, groovy, hirsute, jammy, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 880, released 168, not-affected 152, ignored 25. https://ubuntu.com/security/CVE-2020-12771

Affected software / configurations for CVE-2020-12771

Vendor Product Version Raw CPE
linux linux_kernel <= 5.6.11 cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
opensuse leap 15.1 cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
opensuse leap 15.2 cpe:2.3:o:opensuse:leap:15.2:*:*:*:*:*:*:*
canonical ubuntu_linux 14.04 cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:esm:*:*:*
canonical ubuntu_linux 16.04 cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:esm:*:*:*
canonical ubuntu_linux 18.04 cpe:2.3:o:canonical:ubuntu_linux:18.04:*:*:*:lts:*:*:*
canonical ubuntu_linux 20.04 cpe:2.3:o:canonical:ubuntu_linux:20.04:*:*:*:lts:*:*:*
netapp active_iq_unified_manager — cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*
netapp cloud_backup — cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*
netapp element_software — cpe:2.3:a:netapp:element_software:-:*:*:*:*:*:*:*
netapp hci_management_node — cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:*
netapp solidfire — cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*
netapp steelstore_cloud_integrated_storage — cpe:2.3:a:netapp:steelstore_cloud_integrated_storage:-:*:*:*:*:*:*:*
netapp hci_bootstrap_os — cpe:2.3:o:netapp:hci_bootstrap_os:-:*:*:*:*:*:*:*
netapp a700s_firmware — cpe:2.3:o:netapp:a700s_firmware:-:*:*:*:*:*:*:*
netapp h300s_firmware — cpe:2.3:o:netapp:h300s_firmware:-:*:*:*:*:*:*:*
netapp h500s_firmware — cpe:2.3:o:netapp:h500s_firmware:-:*:*:*:*:*:*:*
netapp h700s_firmware — cpe:2.3:o:netapp:h700s_firmware:-:*:*:*:*:*:*:*
netapp h300e_firmware — cpe:2.3:o:netapp:h300e_firmware:-:*:*:*:*:*:*:*
netapp h500e_firmware — cpe:2.3:o:netapp:h500e_firmware:-:*:*:*:*:*:*:*
netapp h700e_firmware — cpe:2.3:o:netapp:h700e_firmware:-:*:*:*:*:*:*:*
netapp h410s_firmware — cpe:2.3:o:netapp:h410s_firmware:-:*:*:*:*:*:*:*
netapp h410c_firmware — cpe:2.3:o:netapp:h410c_firmware:-:*:*:*:*:*:*:*
netapp h610c_firmware — cpe:2.3:o:netapp:h610c_firmware:-:*:*:*:*:*:*:*
netapp h610s_firmware — cpe:2.3:o:netapp:h610s_firmware:-:*:*:*:*:*:*:*
netapp h615c_firmware — cpe:2.3:o:netapp:h615c_firmware:-:*:*:*:*:*:*:*
oracle sd-wan_edge 8.2 cpe:2.3:a:oracle:sd-wan_edge:8.2:*:*:*:*:*:*:*

References for CVE-2020-12771

URL Tags
http://lists.opensuse.org/opensuse-security-announce/2020-07/msg00071.html Mailing List Third Party Advisory
http://lists.opensuse.org/opensuse-security-announce/2020-08/msg00009.html Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/08/msg00019.html Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/10/msg00032.html Mailing List Third Party Advisory
https://lists.debian.org/debian-lts-announce/2020/10/msg00034.html Mailing List Third Party Advisory
https://lkml.org/lkml/2020/4/26/87 Exploit Mailing List Patch Third Party Advisory
https://security.netapp.com/advisory/ntap-20200608-0001/ Third Party Advisory
https://usn.ubuntu.com/4462-1/ Third Party Advisory
https://usn.ubuntu.com/4463-1/ Third Party Advisory
https://usn.ubuntu.com/4465-1/ Third Party Advisory
https://usn.ubuntu.com/4483-1/ Third Party Advisory
https://usn.ubuntu.com/4485-1/ Third Party Advisory
https://www.oracle.com/security-alerts/cpuApr2021.html Patch Third Party Advisory
cvelogic Threat Intelligence