CVE-2021-3491

Summary

CVECVE-2021-3491
StatePUBLIC
Assigner[email protected]
Source PriorityCVE Program / NVD first with legacy fallback
Published2021-06-04 02:15:00 UTC
Updated2021-09-14 14:31:00 UTC
DescriptionThe io_uring subsystem in the Linux kernel allowed the MAX_RW_COUNT limit to be bypassed in the PROVIDE_BUFFERS operation, which led to negative values being usedin mem_rw when reading /proc/<PID>/mem. This could be used to create a heap overflow leading to arbitrary code execution in the kernel. It was addressed via commit d1f82808877b ("io_uring: truncate lengths larger than MAX_RW_COUNT on provide buffers") (v5.13-rc1) and backported to the stable kernels in v5.12.4, v5.11.21, and v5.10.37. It was introduced in ddf0322db79c ("io_uring: add IORING_OP_PROVIDE_BUFFERS") (v5.7-rc1).

Risk And Classification

Problem Types: CWE-787

NVD Known Affected Configurations (CPE 2.3)

TypeVendorProductVersionUpdateEditionLanguage
Operating System Canonical Ubuntu Linux 20.04 All All All
Operating System Canonical Ubuntu Linux 20.10 All All All
Operating System Canonical Ubuntu Linux 21.04 All All All
Operating System Linux Linux Kernel All All All All

References

ReferenceSourceLinkTags
USN-4950-1: Linux kernel vulnerabilities | Ubuntu security notices | Ubuntu UBUNTU ubuntu.com
USN-4949-1: Linux kernel vulnerabilities | Ubuntu security notices | Ubuntu UBUNTU ubuntu.com
June 2021 Linux Kernel 5.12.4 Vulnerabilities in NetApp Products | NetApp Product Security CONFIRM security.netapp.com
ZDI-21-589 | Zero Day Initiative MISC www.zerodayinitiative.com
kernel/git/torvalds/linux.git - Linux kernel source tree MISC git.kernel.org
oss-security - CVE-2021-3491 - Linux kernel io_uring PROVIDE_BUFFERS MAX_RW_COUNT bypass MLIST www.openwall.com
CVE Program record CVE.ORG www.cve.org canonical
NVD vulnerability detail NVD nvd.nist.gov canonical, analysis

Vendor Comments And Credit

Discovery Credit

LEGACY: Billy Jheng Bing-Jhong (@st424204) of STAR Labs working with Trend Micro's Zero Day Initiative

Legacy QID Mappings

  • 179949 Debian Security Update for linux (CVE-2021-3491)
  • 198365 Ubuntu Security Notification for Linux kernel (OEM) vulnerabilities (USN-4948-1)
  • 198366 Ubuntu Security Notification for Linux kernel vulnerabilities (USN-4949-1)
  • 198367 Ubuntu Security Notification for Linux kernel vulnerabilities (USN-4950-1)
  • 281159 Fedora Security Update for kernel (FEDORA-2021-05152dbcf5)
  • 281160 Fedora Security Update for kernel (FEDORA-2021-286375de1e)
  • 353158 Amazon Linux Security Advisory for kernel : ALAS2KERNEL-5.10-2022-002
  • 353159 Amazon Linux Security Advisory for kernel : ALAS2KERNEL-5.10-2022-001
  • 610362 Google Pixel Android September 2021 Security Patch Missing
  • 6140097 AWS Bottlerocket Security Update for kernel (GHSA-crg3-8994-x9c3)
  • 750117 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:1891-1)
  • 750118 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:1890-1)
  • 750121 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:1888-1)
  • 750125 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:1887-1)
  • 750126 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:1889-1)
  • 750139 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:1913-1)
  • 750140 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:1912-1)
  • 750171 OpenSUSE Security Update for the Linux Kernel (openSUSE-SU-2021:0843-1)
  • 750650 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:1975-1)
  • 750652 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:1977-1)
  • 750741 OpenSUSE Security Update for the Linux Kernel (openSUSE-SU-2021:0947-1)
  • 750762 OpenSUSE Security Update for the Linux Kernel (openSUSE-SU-2021:1977-1)
  • 750766 OpenSUSE Security Update for the Linux Kernel (openSUSE-SU-2021:1975-1)
  • 750864 SUSE Enterprise Linux Security Update for the Linux Kernel (SUSE-SU-2021:2421-1)
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