CVE-2021-20239: Buffer Overflow
First published: Mon Feb 01 2021(Updated: )
A flaw was found in the Linux kernel in versions before 5.4.92 in the BPF protocol. This flaw allows an attacker with a local account to leak information about kernel internal addresses. The highest threat from this vulnerability is to confidentiality.
Credit: secalert@redhat.com
| Affected Software | Affected Version | How to fix |
|---|---|---|
| redhat/kernel | <5.4.92 | 5.4.92 |
| Linux kernel | <5.4.92 | |
| Red Hat Enterprise Linux | =5.0 | |
| Red Hat Enterprise Linux | =6.0 | |
| Red Hat Enterprise Linux | =8.0 | |
| Fedora | =33 | |
| debian/linux | 5.10.223-1 5.10.234-1 6.1.123-1 6.1.128-1 6.12.12-1 6.12.16-1 |
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://bugzilla.redhat.com/show_bug.cgi?id=1923636
- https://launchpad.net/bugs/cve/CVE-2021-20239
- https://www.zerodayinitiative.com/advisories/ZDI-21-100/
- https://gist.github.com/Ga-ryo/2ec958e78f55c5d18558960f3fe1c6ec
- https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=1923640
- https://access.redhat.com/errata/RHSA-2021:4140
- https://access.redhat.com/errata/RHSA-2021:4356
- https://security-tracker.debian.org/tracker/CVE-2021-20239
- https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-20239
- https://nvd.nist.gov/vuln/detail/CVE-2021-20239
- https://ubuntu.com/security/CVE-2021-20239
Frequently Asked Questions
What is the severity of CVE-2021-20239?
The severity of CVE-2021-20239 is high due to its potential impact on confidentiality.
How do I fix CVE-2021-20239?
To fix CVE-2021-20239, you need to upgrade to Linux kernel version 5.4.92 or later.
Who is affected by CVE-2021-20239?
CVE-2021-20239 affects Linux kernel versions prior to 5.4.92, impacting systems using Red Hat Enterprise Linux and Fedora.
What type of attack can exploit CVE-2021-20239?
CVE-2021-20239 can be exploited by an attacker with local access, allowing them to leak internal kernel addresses.
Is CVE-2021-20239 patched in all distributions?
CVE-2021-20239 has been patched in several distributions, but users should verify their specific distribution for an available update.
- agent/type
- agent/remedy
- agent/first-publish-date
- collector/launchpad-cve
- source/Launchpad
- agent/severity
- agent/weakness
- collector/redhat-bugzilla
- source/Red Hat
- alias/CVE-2021-20239
- agent/software-canonical-lookup
- collector/mitre-cve
- source/MITRE
- agent/references
- agent/last-modified-date
- agent/trending
- agent/source
- agent/author
- collector/usn-cve
- source/Ubuntu
- agent/description
- agent/event
- agent/tags
- agent/softwarecombine
- collector/security-tracker-debian
- source/Debian
- collector/nvd-cve
- source/NVD
- agent/software-canonical-lookup-request
- collector/nvd-index
- package-manager/redhat
- package-manager/debian
- vendor/linux
- canonical/linux kernel
- vendor/redhat
- canonical/red hat enterprise linux
- version/red hat enterprise linux/5.0
- version/red hat enterprise linux/6.0
- version/red hat enterprise linux/8.0
- vendor/fedoraproject
- canonical/fedora
- version/fedora/33