CVE-2020-12657: linux linux_kernel Use After Free

Modified

AliasesRHSA-2020:2427RHSA-2020:2428RHSA-2020:2567+4 more

Published 05-05-2020Last modified 04-08-2024

Vulnerability summary

CVE-2020-12657 is a high (CVSS 7.8) Use After Free vulnerability in linux linux_kernel. EPSS estimates a 0.71% chance of exploitation in the next 30 days, higher than 53.6% of scored vulnerabilities.

Priority

Routine

Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?

CVSS score

7.8/10

010

High · v3.1 (NVD)

EPSS score

0.71%

0%100%

Low · 0.00 pp in 30 days

KEVNot listedNot listed by any tracked catalog.

RansomwareNot flaggedNo ransomware use recorded.

Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 16 · Related 15

OPENSUSE-SU-2020:0801-1 RHSA-2020:2429 SUSE-SU-2020:1587-1 SUSE-SU-2020:1599-1 SUSE-SU-2020:1602-1 SUSE-SU-2020:1603-1+10 more

Timeline

05-05-2020
PublishedVulnerability first disclosed.
04-08-2024
Last modifiedVulnerability information updated.

Description

An issue was discovered in the Linux kernel before 5.6.5. There is a use-after-free in block/bfq-iosched.c related to bfq_idle_slice_timer_body.

CVSS metrics

5 scores · 4 sources · 2 versions

v3.17.8v2.04.6

EPSS trend

Probability

0.71%

Chance of exploitation in the next 30 days

Percentile

54%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.71% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs

CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Redhat68 products

bpftool< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
bpftool-debuginfo< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-abi-whitelists< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-core< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1

kernel-debug< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-debug-core< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-debug-debuginfo< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-debug-devel< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-debug-modules< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-debug-modules-extra< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-debuginfo< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-debuginfo-common-aarch64< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-debuginfo-common-ppc64le< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-debuginfo-common-s390x< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-debuginfo-common-x86_64< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-devel< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-doc< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-modules< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-modules-extra< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-rt< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-core< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-debug< 0:4.18.0-193.6.3.rt13.59.el8_2
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kernel-rt-debug-debuginfo< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-debug-devel< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-debug-kvm< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-debug-modules< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-debug-modules-extra< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-debuginfo< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-debuginfo-common-x86_64< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-devel< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-kvm< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-modules< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-rt-modules-extra< 0:4.18.0-193.6.3.rt13.59.el8_2
kernel-tools< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-tools-debuginfo< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-tools-libs< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-tools-libs-devel< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-zfcpdump< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-zfcpdump-core< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-zfcpdump-debuginfo< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-zfcpdump-devel< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-zfcpdump-modules< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kernel-zfcpdump-modules-extra< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
kpatch-patch-4_18_0-147< 0:1-14.el8
kpatch-patch-4_18_0-147_0_2< 0:1-10.el8
kpatch-patch-4_18_0-147_0_2-debuginfo< 0:1-10.el8
kpatch-patch-4_18_0-147_0_2-debugsource< 0:1-10.el8
kpatch-patch-4_18_0-147_0_3< 0:1-10.el8
kpatch-patch-4_18_0-147_13_2< 0:1-1.el8_1
kpatch-patch-4_18_0-147_13_2-debuginfo< 0:1-1.el8_1
kpatch-patch-4_18_0-147_13_2-debugsource< 0:1-1.el8_1
kpatch-patch-4_18_0-147_3_1< 0:1-10.el8_1
kpatch-patch-4_18_0-147_5_1< 0:1-5.el8_1
kpatch-patch-4_18_0-147_8_1< 0:1-3.el8_1
kpatch-patch-4_18_0-147-debuginfo< 0:1-14.el8
kpatch-patch-4_18_0-147-debugsource< 0:1-14.el8
kpatch-patch-4_18_0-193< 0:1-3.el8
kpatch-patch-4_18_0-193_1_2< 0:1-1.el8_2
kpatch-patch-4_18_0-193_1_2-debuginfo< 0:1-1.el8_2
kpatch-patch-4_18_0-193_1_2-debugsource< 0:1-1.el8_2
kpatch-patch-4_18_0-193-debuginfo< 0:1-3.el8
kpatch-patch-4_18_0-193-debugsource< 0:1-3.el8
perf< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
perf-debuginfo< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
python3-perf< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1
python3-perf-debuginfo< 0:4.18.0-193.6.3.el8_2 | < 0:4.18.0-147.20.1.el8_1