CVE-2021-4090

Description

An out-of-bounds (OOB) memory write flaw was found in the NFSD in the Linux kernel. Missing sanity may lead to a write beyond bmval[bmlen-1] in nfsd4_decode_bitmap4 in fs/nfsd/nfs4xdr.c. In this flaw, a local attacker with user privilege may gain access to out-of-bounds memory, leading to a system integrity and confidentiality threat.

CVSS Metrics

• v3.1•HIGH•Score: 7.1CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N
• v2.0•MEDIUM•Score: 6.6AV:L/AC:L/Au:N/C:C/I:C/A:N

EPSS Trends

Current EPSS score: 0.07%• Percentile: 22%

Techniques & Countermeasures

• CWE-787•Out-of-bounds Write

  The product writes data past the end, or before the beginning, of the intended buffer.

Affected Systems

• linux•linux_kernel

  < 5.16 | 5.16 | 5.16:rc1

• netapp•h300e

  na

• netapp•h300s_firmware

  na

• netapp•h410c_firmware

  na

• netapp•h410s_firmware

  na

• netapp•h500e

  na

• netapp•h500s_firmware

  na

• netapp•h700e

  na

• netapp•h700s_firmware

  na

References (4)

• https://bugzilla.redhat.com/show_bug.cgi?id=2025101
• https://lore.kernel.org/linux-nfs/163692036074.16710.5678362976688977923.stgit%40klimt.1015granger.net/
• https://security.netapp.com/advisory/ntap-20220318-0010/
• https://cert-portal.siemens.com/productcert/html/ssa-265688.html