CVE-2021-47461: userfaultfd: fix a race between writeprotect and exit_mmap()
First published: Wed May 22 2024(Updated: )
In the Linux kernel, the following vulnerability has been resolved: userfaultfd: fix a race between writeprotect and exit_mmap() A race is possible when a process exits, its VMAs are removed by exit_mmap() and at the same time userfaultfd_writeprotect() is called. The race was detected by KASAN on a development kernel, but it appears to be possible on vanilla kernels as well. Use mmget_not_zero() to prevent the race as done in other userfaultfd operations.
Credit: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
| Affected Software | Affected Version | How to fix |
|---|---|---|
| redhat/kernel | <5.10.76 | 5.10.76 |
| redhat/kernel | <5.14.15 | 5.14.15 |
| redhat/kernel | <5.15 | 5.15 |
| IBM Security Verify Governance - Identity Manager | <=ISVG 10.0.2 | |
| IBM Security Verify Governance, Identity Manager Software Stack | <=ISVG 10.0.2 | |
| IBM Security Verify Governance, Identity Manager Virtual Appliance | <=ISVG 10.0.2 | |
| IBM Security Verify Governance Identity Manager Container | <=ISVG 10.0.2 |
Never miss a vulnerability like this again
Sign up to SecAlerts for real-time vulnerability data matched to your software, aggregated from hundreds of sources.
Reference Links
- https://git.kernel.org/stable/c/149958ecd0627a9f1e9c678c25c665400054cd6a
- https://git.kernel.org/stable/c/3cda4bfffd4f755645577aaa9e96a606657b4525
- https://git.kernel.org/stable/c/cb185d5f1ebf900f4ae3bf84cee212e6dd035aca
- https://access.redhat.com/security/cve/CVE-2021-47461
- https://lore.kernel.org/linux-cve-announce/2024052225-CVE-2021-47461-a472@gregkh/T
- https://access.redhat.com/errata/RHSA-2024:5102
- https://access.redhat.com/errata/RHSA-2024:5101
- https://access.redhat.com/errata/RHSA-2024:6297
- https://access.redhat.com/errata/RHSA-2024:10262
- https://bugzilla.redhat.com/show_bug.cgi?id=2282896
- https://www.ibm.com/support/pages/node/7230443 (Advisory)
Frequently Asked Questions
What is the severity of CVE-2021-47461?
CVE-2021-47461 is classified with a medium severity due to its potential impact on system stability.
How do I fix CVE-2021-47461?
To fix CVE-2021-47461, update the kernel to version 5.10.76, 5.14.15, or 5.15.
What systems are affected by CVE-2021-47461?
CVE-2021-47461 affects various Linux kernel versions and IBM Security Verify Governance versions up to 10.0.2.
What specific issue does CVE-2021-47461 address?
CVE-2021-47461 addresses a race condition between userfaultfd_writeprotect() and exit_mmap() in the Linux kernel.
Is CVE-2021-47461 specific to certain distributions?
Yes, CVE-2021-47461 is primarily reported in Red Hat kernels and certain IBM security products.
- agent/title
- agent/type
- agent/first-publish-date
- agent/author
- collector/nvd-api
- source/NVD
- agent/severity
- collector/redhat-bugzilla
- source/Red Hat
- alias/CVE-2021-47461
- agent/software-canonical-lookup
- collector/mitre-cve
- source/MITRE
- agent/last-modified-date
- agent/weakness
- agent/references
- agent/source
- agent/softwarecombine
- agent/description
- agent/tags
- agent/event
- collector/ibm-support
- source/IBM
- agent/software-canonical-lookup-request
- package-manager/redhat
- vendor/ibm
- canonical/ibm security verify governance - identity manager
- version/ibm security verify governance - identity manager/isvg 10.0.2
- canonical/ibm security verify governance, identity manager software stack
- version/ibm security verify governance, identity manager software stack/isvg 10.0.2
- canonical/ibm security verify governance, identity manager virtual appliance
- version/ibm security verify governance, identity manager virtual appliance/isvg 10.0.2
- canonical/ibm security verify governance identity manager container
- version/ibm security verify governance identity manager container/isvg 10.0.2