CVE-2020-36387: linux linux_kernel Use After Free
CVSS: 7.8v3.1HighModified
AliasesUBUNTU-CVE-2020-36387DEBIAN-CVE-2020-36387
Published 07-06-2021Last modified 04-08-2024
Vulnerability summary
CVE-2020-36387 is a high (CVSS 7.8) Use After Free vulnerability in linux linux_kernel. EPSS estimates a 0.39% chance of exploitation in the next 30 days, higher than 31.8% of scored vulnerabilities.
CVSS score
7.8/10
010
High · v3.1 (NVD)EPSS score
0.39%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 07-06-2021PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
An issue was discovered in the Linux kernel before 5.8.2. fs/io_uring.c has a use-after-free related to io_async_task_func and ctx reference holding, aka CID-6d816e088c35.
CVSS metrics
4 scores · 3 sources · 2 versionsHigh 7.8Preferred score · NVD (NIST)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
High 7.2Preferred score · NVD (NIST)
AV:L/AC:L/Au:N/C:C/I:C/A:CSourcesSingle source
EPSS trend
Probability
0.39%
Chance of exploitation in the next 30 days
Percentile
32%
Versus all other CVEs
30-day change
0.00 pp
From 0.39% on 20-09-2026
20-09-202620-10-2026
EPSS score0.39%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Ubuntu17 products
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.3All versions (No fix recorded)
- linux-azureAll versions (No fix recorded)
- linux-azure-5.3All versions (No fix recorded)
- linux-azure-edgeAll versions (No fix recorded)
Debian1 product
- linux< 5.7.17-1
Linux1 product
- linux_kernel≥ 5.7, < 5.7.16 | ≥ 5.8, < 5.8.2
4 vendors · 27 products
References
9 links- cdn.kernel.org/pub/linux/kernel/v5.x/ChangeLog-5.8.2X Refsource MISCREPORTMailing ListPatchRelease NotesVendor Advisory
- syzkaller.appspot.com/bug?id=ce5f07d6ec3b5050b8f0728a3b389aa510f2591bX Refsource MISCREPORTPatchThird Party Advisory
- sites.google.com/view/syzscope/kasan-use-after-free-read-in-io_async_task_funcX Refsource MISCREPORTPatchThird Party Advisory
