What is CVE-2021-47107?

CVE-2021-47107 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10, affecting Linux kernel versions from 5.13 onward and patched in 5.15.12 and 5.16. CVE-2021-47107 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2021-47107?

CVE-2021-47107 has a CVSS score of 7.8 out of 10, rated High severity. The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Is there a patch available for CVE-2021-47107?

Yes, CVE-2021-47107 has been patched. Fixed versions include 5.15.12 and 5.16. If you are running Linux kernel 5.13 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2021-47107 actively exploited?

CVE-2021-47107 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2021-47107

High

In the Linux kernel, the following vulnerability has been resolved: NFSD: Fix READDIR buffer overflow If a client sends a READDIR count argument that is too small (say, zero), then the buffer size calculation in the new init_dirlist helper functions results in an underflow, allowing the XDR stream functions to write beyond the actual buffer. This calculation has always been suspect. NFSD has never sanity- checked the READDIR count argument, but the old entry encoders managed the problem correctly. With the commits below, entry encoding changed, exposing the underflow to the pointer arithmetic in xdr_reserve_space(). Modern NFS clients attempt to retrieve as much data as possible for each READDIR request. Also, we have no unit tests that exercise the behavior of READDIR at the lower bound of @count values. Thus this case was missed during testing.

Package Linux Kernel

Published 2024-03-04

Last modified 2026-05-12

CVSS version 3.1

Patch available

Yes

CVSS 3.1 score

7.8

out of 10

High

Attack Vector

Local

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Unchanged

Confidentiality

High

Integrity

High

Availability

High

Vector string

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness type

CWE-120

CVE-2021-47107 is classified as CWE-120

See CWE-120 on MITRE CWE for full details on this weakness type.

Affected versions

Linux kernel versions 5.13 and later are affected. Fixed in 5.15.12, 5.16 and their respective stable series.

Affected from

≥ 5.13

Fixed in

✓ 5.15.12 5.15.x ✓ 5.16

References

4 total

Kernel Git
https://git.kernel.org/stable/c/53b1119a6e5028b125f431a0116ba73510d82a72

Exploit Mailing List Patch
Kernel Git
https://git.kernel.org/stable/c/9e291a6a28d32545ed2fd959a8165144d1724df1

Exploit Mailing List Patch
Kernel Git
https://git.kernel.org/stable/c/eabc0aab98e5218ceecd82069b0d6fdfff5ee885

Exploit Mailing List Patch
Cert-Portal
https://cert-portal.siemens.com/productcert/html/ssa-265688.html

Details

CVE ID CVE-2021-47107

Severity High

CVSS score 7.8 / 10

CVSS version 3.1

Published 2024-03-04

Modified 2026-05-12

KEV No

Patch

Yes

Package linux

Frequently asked questions

What is CVE-2021-47107?

CVE-2021-47107 is a High severity Linux kernel vulnerability with a CVSS score of 7.8 out of 10 . It affects Linux kernel versions from 5.13 onward and has been patched in 5.15.12 and 5.16. CVE-2021-47107 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
What is the CVSS score for CVE-2021-47107?

CVE-2021-47107 has a CVSS score of 7.8 out of 10, rated High severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Is there a patch available for CVE-2021-47107?

Yes. CVE-2021-47107 has been patched. Fixed versions include 5.15.12 and 5.16. If you are running Linux kernel 5.13 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2021-47107 actively exploited?

No. CVE-2021-47107 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.