// For flags

CVE-2021-47316

nfsd: fix NULL dereference in nfs3svc_encode_getaclres

Severity Score

"-"
*CVSS v-

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

In the Linux kernel, the following vulnerability has been resolved:

nfsd: fix NULL dereference in nfs3svc_encode_getaclres

In error cases the dentry may be NULL.

Before 20798dfe249a, the encoder also checked dentry and
d_really_is_positive(dentry), but that looks like overkill to me--zero
status should be enough to guarantee a positive dentry.

This isn't the first time we've seen an error-case NULL dereference
hidden in the initialization of a local variable in an xdr encoder. But
I went back through the other recent rewrites and didn't spot any
similar bugs.

En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: nfsd: corrige la desreferencia NULL en nfs3svc_encode_getaclres. En casos de error, la dentry puede ser NULL. Antes de 20798dfe249a, el codificador también verificaba dentry y d_really_is_positive(dentry), pero eso me parece excesivo: el estado cero debería ser suficiente para garantizar un dentry positivo. Esta no es la primera vez que vemos una desreferencia NULL de caso de error oculta en la inicialización de una variable local en un codificador xdr. Pero revisé las otras reescrituras recientes y no encontré ningún error similar.

*Credits: N/A
CVSS Scores
Attack Vector
-
Attack Complexity
-
Privileges Required
-
User Interaction
-
Scope
-
Confidentiality
-
Integrity
-
Availability
-
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-05-21 CVE Reserved
  • 2024-05-21 CVE Published
  • 2024-06-22 EPSS Updated
  • 2024-08-04 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.13 < 5.13.4
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.13 < 5.13.4"
en
Affected
Linux
Search vendor "Linux"
 Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
 >= 5.13 < 5.14
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.13 < 5.14"
en
Affected