medium 5.7

CVE-2020-14311 json

There is an issue with grub2 before version 2.06 while handling symlink on ext filesystems.

published 2020-07-31 6 y ago modified 2026-06-17 4 mo ago also EUVD-2020-6463

cvss: 5.7; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.5%; EPSS 0.5% chance of exploitation in 30 days, percentile 40%
public exploits: 0; none known

There is an issue with grub2 before version 2.06 while handling symlink on ext filesystems. A filesystem containing a symbolic link with an inode size of UINT32_MAX causes an arithmetic overflow leading to a zero-sized memory allocation with subsequent heap-based buffer overflow.

Patch / fix

fixed in 1 distros 7

gnu grub2 2.06

debian ubuntu red hat suse opensuse alpine azure linux

grub2 Debian 14, Debian 13, Debian 12 2.04-9

debian advisories DEBIAN-CVE-2020-14311

grub2 Ubuntu 16.04 LTS 2.02~beta2-36ubuntu3.26
grub2 Ubuntu 18.04 LTS 2.02-2ubuntu8.16
grub2 Ubuntu 20.04 LTS 2.04-1ubuntu26.1
grub2-signed Ubuntu 16.04 LTS 1.66.26
grub2-signed Ubuntu 18.04 LTS 1.93.18
grub2-signed Ubuntu 20.04 LTS 1.142.3
grub2-unsigned Ubuntu 20.04 LTS, Ubuntu 18.04 LTS 2.04-1ubuntu47.4
grub2 Ubuntu Pro 14.04 LTS 2.02~beta2-9ubuntu1.20

ubuntu advisories UBUNTU-CVE-2020-14311

Ubuntu security data © Canonical Ltd., from https://github.com/canonical/ubuntu-security-notices via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

grub2 RHEL 7 1:2.02-0.86.el7_8
shim RHEL 7 15-7.el7_9
mokutil RHEL 7 15-7.el7_8
fwupdate RHEL 7 12-6.el7_8
grub2-pc RHEL 7 1:2.02-0.86.el7_8
shim-x64 RHEL 7 15-7.el7_8
shim-ia32 RHEL 7 15-7.el7_8
grub2-ppc64 RHEL 7 1:2.02-0.86.el7_8

red hat advisories RHSA-2020:3273 RHSA-2020:3276 RHSA-2020:3274 RHSA-2020:3271 RHSA-2020:3275 RHSA-2020:3217

grub2 SLES for SAP 12 SP3, SLES 12 SP3-LTSS, SLES 12 SP3-BCL +4 more 2.02-4.53.1
grub2 SLES for SAP 12 SP5, SLES for SAP 12 SP4, SLES 12 SP5 +3 more 2.02-12.31.1
grub2 SLE Module for Server Applications 15 SP1, SLE Module for Basesystem 15 SP1 2.02-26.25.1
grub2 SLES for SAP 12 SP2, SLES 12 SP2-LTSS, SLES 12 SP2-BCL +1 more 2.02~beta2-115.49.1
grub2 SLE Module for Server Applications 15 SP2, SLE Module for Basesystem 15 SP2 2.04-9.7.1
grub2 SLES for SAP 15, SLES 15-LTSS, SLE High Performance Computing 15-LTSS +1 more 2.02-19.48.1
grub2 SLES 11 SP4-LTSS 2.00-0.66.15.1

suse advisories SUSE-SU-2020:2079-1 SUSE-SU-2020:2078-1 SUSE-SU-2020:2077-1 SUSE-SU-2020:2076-1 SUSE-SU-2020:14440-1 SUSE-SU-2020:2074-1

grub2 openSUSE Leap 15.2 2.04-lp152.7.3.4
grub2 openSUSE Leap 15.1 2.02-lp151.21.21.4

opensuse advisories openSUSE-SU-2020:1169-1 openSUSE-SU-2020:1168-1

grub Alpine 3.24, Alpine 3.23, Alpine 3.22 +5 more 2.06-r0

alpine advisories ALPINE-CVE-2020-14311

Alpine secdb © Alpine Linux, from https://secdb.alpinelinux.org via OSV; changed: normalised to fixed package versions per release. CC BY-SA 4.0

grub2 CBL-Mariner 2.0 2.06~rc1-7

azure linux advisories AZL-6459

Azure Linux vulnerability data, Copyright (c) Microsoft Corporation, from https://github.com/microsoft/AzureLinuxVulnerabilityData via OSV, under the MIT licence; changed: normalised to fixed package versions per release. MIT

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2020-14311 updated 2026-02-23 cvss 5.7

grub2: Integer overflow in grub_ext2_read_link leads to heap-based buffer overflow

Red Hat CodeReady Linux Builder (v. 8) shim-unsigned-x64 15-7.el8
fixed: vendor fix RHSA-2020:3216
Red Hat CodeReady Linux Builder EUS (v. 8.1) shim-unsigned-x64 15-7.el8
fixed: vendor fix RHSA-2020:3223
Red Hat Enterprise Linux BaseOS (v. 8) shim 15-14.el8_2, fwupd 1.1.4-7.el8_2, grub2 2.02-87.el8_2, shim-x64 15-14.el8_2, shim-aa64 15-14.el8_2, shim-ia32 15-14.el8_2, +18 more
fixed: vendor fix RHSA-2020:3216
Red Hat Enterprise Linux BaseOS E4S (v. 8.0) shim 15-14.el8_0, fwupd 1.1.4-2.el8_0, grub2 2.02-87.el8_0, shim-x64 15-14.el8_0, shim-ia32 15-14.el8_0, grub2-pc 2.02-87.el8_0, +15 more
fixed: vendor fix RHSA-2020:3227
Red Hat Enterprise Linux BaseOS EUS (v. 8.1) shim 15-14.el8_1, fwupd 1.1.4-2.el8_1, grub2 2.02-87.el8_1, shim-x64 15-14.el8_1, shim-aa64 15-14.el8_1, shim-ia32 15-14.el8_1, +18 more
fixed: vendor fix RHSA-2020:3223
Red Hat Enterprise Linux Client (v. 7) shim 15-7.el7_9, mokutil 15-7.el7_8, fwupdate 12-6.el7_8, shim-x64 15-7.el7_8, shim-ia32 15-7.el7_8, grub2 2.02-0.86.el7_8, +23 more Red Hat Enterprise Linux Client Optional (v. 7) fwupdate 12-6.el7_8, grub2 2.02-0.86.el7_8, fwupdate-efi 12-6.el7_8, fwupdate-libs 12-6.el7_8, grub2-pc 2.02-0.86.el7_8, grub2-ppc64 2.02-0.86.el7_8, +16 more Red Hat Enterprise Linux ComputeNode (v. 7) shim 15-7.el7_9, mokutil 15-7.el7_8, fwupdate 12-6.el7_8, shim-x64 15-7.el7_8, shim-ia32 15-7.el7_8, grub2 2.02-0.86.el7_8, +23 more
fixed: vendor fix RHSA-2020:3217
Red Hat Enterprise Linux ComputeNode EUS (v. 7.6) shim 15-8.el7, mokutil 15-8.el7_6, fwupdate 12-6.el7_6, shim-x64 15-8.el7_6, shim-ia32 15-8.el7_6, grub2 2.02-0.86.el7_6, +23 more
fixed: vendor fix RHSA-2020:3271
Red Hat Enterprise Linux ComputeNode EUS (v. 7.7) shim 15-8.el7, mokutil 15-8.el7_7, fwupdate 12-6.el7_7, shim-x64 15-8.el7_7, shim-ia32 15-8.el7_7, grub2 2.02-0.86.el7_7, +23 more
fixed: vendor fix RHSA-2020:3274

show 25 more

Red Hat Enterprise Linux ComputeNode Optional (v. 7) fwupdate 12-6.el7_8, grub2 2.02-0.86.el7_8, fwupdate-efi 12-6.el7_8, fwupdate-libs 12-6.el7_8, grub2-pc 2.02-0.86.el7_8, grub2-ppc64 2.02-0.86.el7_8, +16 more
fixed: vendor fix RHSA-2020:3217
Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.6) fwupdate 12-6.el7_6, grub2 2.02-0.86.el7_6, fwupdate-efi 12-6.el7_6, fwupdate-libs 12-6.el7_6, grub2-pc 2.02-0.86.el7_6, grub2-ppc64 2.02-0.86.el7_6, +16 more
fixed: vendor fix RHSA-2020:3271
Red Hat Enterprise Linux ComputeNode Optional EUS (v. 7.7) fwupdate 12-6.el7_7, grub2 2.02-0.86.el7_7, fwupdate-efi 12-6.el7_7, fwupdate-libs 12-6.el7_7, grub2-pc 2.02-0.86.el7_7, grub2-ppc64 2.02-0.86.el7_7, +16 more
fixed: vendor fix RHSA-2020:3274
Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server (v. 7) grub2 2.02-0.86.el7_6, grub2-pc 2.02-0.86.el7_6, grub2-ppc64 2.02-0.86.el7_6, grub2-tools 2.02-0.86.el7_6, grub2-common 2.02-0.86.el7_6, grub2-efi-x64 2.02-0.86.el7_6, +13 more Red Hat Enterprise Linux for ARM and IBM Power LE (POWER9) Server Optional (v. 7) grub2 2.02-0.86.el7_6, grub2-pc 2.02-0.86.el7_6, grub2-ppc64 2.02-0.86.el7_6, grub2-tools 2.02-0.86.el7_6, grub2-common 2.02-0.86.el7_6, grub2-efi-x64 2.02-0.86.el7_6, +13 more
fixed: vendor fix RHSA-2020:3271
Red Hat Enterprise Linux Server (v. 7) shim 15-7.el7_9, mokutil 15-7.el7_8, fwupdate 12-6.el7_8, shim-x64 15-7.el7_8, shim-ia32 15-7.el7_8, grub2 2.02-0.86.el7_8, +23 more
fixed: vendor fix RHSA-2020:3217
Red Hat Enterprise Linux Server AUS (v. 7.2) shim 15-8.el7, shim 15-8.el7_2, mokutil 15-8.el7_2, grub2 2.02-0.86.el7_2, shim-signed 15-8.el7_2, grub2-pc 2.02-0.86.el7_2, +17 more
fixed: vendor fix RHSA-2020:3273
Red Hat Enterprise Linux Server AUS (v. 7.3) shim 15-8.el7, shim 15-8.el7_3, mokutil 15-8.el7_3, grub2 2.02-0.86.el7, grub2-pc 2.02-0.86.el7, shim-signed 15-8.el7_3, +17 more
fixed: vendor fix RHSA-2020:3276
Red Hat Enterprise Linux Server AUS (v. 7.4) shim 15-8.el7, mokutil 15-8.el7_4, fwupdate 9-10.el7_4, shim-x64 15-8.el7_4, shim-ia32 15-8.el7_4, grub2 2.02-0.86.el7_4, +21 more
fixed: vendor fix RHSA-2020:3275
Red Hat Enterprise Linux Server E4S (v. 7.3) shim 15-8.el7, shim 15-8.el7_3, mokutil 15-8.el7_3, grub2 2.02-0.86.el7, grub2-pc 2.02-0.86.el7, shim-signed 15-8.el7_3, +18 more
fixed: vendor fix RHSA-2020:3276
Red Hat Enterprise Linux Server E4S (v. 7.4) shim 15-8.el7, mokutil 15-8.el7_4, fwupdate 9-10.el7_4, shim-x64 15-8.el7_4, shim-ia32 15-8.el7_4, grub2 2.02-0.86.el7_4, +22 more
fixed: vendor fix RHSA-2020:3275
Red Hat Enterprise Linux Server EUS (v. 7.6) shim 15-8.el7, mokutil 15-8.el7_6, fwupdate 12-6.el7_6, shim-x64 15-8.el7_6, shim-ia32 15-8.el7_6, grub2 2.02-0.86.el7_6, +23 more
fixed: vendor fix RHSA-2020:3271
Red Hat Enterprise Linux Server EUS (v. 7.7) shim 15-8.el7, mokutil 15-8.el7_7, fwupdate 12-6.el7_7, shim-x64 15-8.el7_7, shim-ia32 15-8.el7_7, grub2 2.02-0.86.el7_7, +23 more
fixed: vendor fix RHSA-2020:3274
Red Hat Enterprise Linux Server Optional (v. 7) fwupdate 12-6.el7_8, grub2 2.02-0.86.el7_8, fwupdate-efi 12-6.el7_8, fwupdate-libs 12-6.el7_8, grub2-pc 2.02-0.86.el7_8, grub2-ppc64 2.02-0.86.el7_8, +16 more
fixed: vendor fix RHSA-2020:3217
Red Hat Enterprise Linux Server Optional AUS (v. 7.2) shim 15-8.el7, grub2 2.02-0.86.el7_2, grub2-pc 2.02-0.86.el7_2, shim-unsigned-x64 15-8.el7, grub2-tools 2.02-0.86.el7_2, shim-unsigned-ia32 15-8.el7, +14 more
fixed: vendor fix RHSA-2020:3273
Red Hat Enterprise Linux Server Optional AUS (v. 7.3) shim 15-8.el7, grub2 2.02-0.86.el7, grub2-pc 2.02-0.86.el7, grub2-tools 2.02-0.86.el7, grub2-common 2.02-0.86.el7, shim-unsigned-x64 15-8.el7, +14 more
fixed: vendor fix RHSA-2020:3276
Red Hat Enterprise Linux Server Optional AUS (v. 7.4) fwupdate 9-10.el7_4, grub2 2.02-0.86.el7_4, fwupdate-efi 9-10.el7_4, fwupdate-libs 9-10.el7_4, grub2-pc 2.02-0.86.el7_4, grub2-tools 2.02-0.86.el7_4, +14 more
fixed: vendor fix RHSA-2020:3275
Red Hat Enterprise Linux Server Optional E4S (v. 7.3) shim 15-8.el7, grub2 2.02-0.86.el7, grub2-pc 2.02-0.86.el7, grub2-tools 2.02-0.86.el7, grub2-common 2.02-0.86.el7, shim-unsigned-x64 15-8.el7, +15 more
fixed: vendor fix RHSA-2020:3276
Red Hat Enterprise Linux Server Optional E4S (v. 7.4) fwupdate 9-10.el7_4, grub2 2.02-0.86.el7_4, fwupdate-efi 9-10.el7_4, fwupdate-libs 9-10.el7_4, grub2-pc 2.02-0.86.el7_4, grub2-tools 2.02-0.86.el7_4, +15 more
fixed: vendor fix RHSA-2020:3275
Red Hat Enterprise Linux Server Optional EUS (v. 7.6) fwupdate 12-6.el7_6, grub2 2.02-0.86.el7_6, fwupdate-efi 12-6.el7_6, fwupdate-libs 12-6.el7_6, grub2-pc 2.02-0.86.el7_6, grub2-ppc64 2.02-0.86.el7_6, +16 more
fixed: vendor fix RHSA-2020:3271
Red Hat Enterprise Linux Server Optional EUS (v. 7.7) fwupdate 12-6.el7_7, grub2 2.02-0.86.el7_7, fwupdate-efi 12-6.el7_7, fwupdate-libs 12-6.el7_7, grub2-pc 2.02-0.86.el7_7, grub2-ppc64 2.02-0.86.el7_7, +16 more
fixed: vendor fix RHSA-2020:3274
Red Hat Enterprise Linux Server Optional TUS (v. 7.3) shim 15-8.el7, grub2 2.02-0.86.el7, grub2-pc 2.02-0.86.el7, grub2-tools 2.02-0.86.el7, grub2-common 2.02-0.86.el7, shim-unsigned-x64 15-8.el7, +14 more
fixed: vendor fix RHSA-2020:3276
Red Hat Enterprise Linux Server Optional TUS (v. 7.4) fwupdate 9-10.el7_4, grub2 2.02-0.86.el7_4, fwupdate-efi 9-10.el7_4, fwupdate-libs 9-10.el7_4, grub2-pc 2.02-0.86.el7_4, grub2-tools 2.02-0.86.el7_4, +14 more
fixed: vendor fix RHSA-2020:3275
Red Hat Enterprise Linux Server TUS (v. 7.3) shim 15-8.el7, shim 15-8.el7_3, mokutil 15-8.el7_3, grub2 2.02-0.86.el7, grub2-pc 2.02-0.86.el7, shim-signed 15-8.el7_3, +17 more
fixed: vendor fix RHSA-2020:3276
Red Hat Enterprise Linux Server TUS (v. 7.4) shim 15-8.el7, mokutil 15-8.el7_4, fwupdate 9-10.el7_4, shim-x64 15-8.el7_4, shim-ia32 15-8.el7_4, grub2 2.02-0.86.el7_4, +21 more
fixed: vendor fix RHSA-2020:3275
Red Hat Enterprise Linux Workstation (v. 7) shim 15-7.el7_9, mokutil 15-7.el7_8, fwupdate 12-6.el7_8, shim-x64 15-7.el7_8, shim-ia32 15-7.el7_8, grub2 2.02-0.86.el7_8, +23 more Red Hat Enterprise Linux Workstation Optional (v. 7) fwupdate 12-6.el7_8, grub2 2.02-0.86.el7_8, fwupdate-efi 12-6.el7_8, fwupdate-libs 12-6.el7_8, grub2-pc 2.02-0.86.el7_8, grub2-ppc64 2.02-0.86.el7_8, +16 more
fixed: vendor fix RHSA-2020:3217

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

cisa ICSA-21-336-06 updated 2021-12-02 cvss 6.0

Hitachi Energy APM Edge

Hitachi Energy APM Edge 3.0, 2.0, 1.0
affected: vendor fix, mitigation “Physically protect process control systems from direct access by unauthorized personnel.” search.abb.com

From CISA ICS and IT advisories (CSAF, https://github.com/cisagov/CSAF), a U.S. Government work; changed: reduced to products, statuses and remediations. CISA notification · csaf

Exploit prediction

0.46% chance of exploitation in the next 30 days, higher than 40% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	5.7	CVSS:3.1/AV:L/AC:H/PR:H/UI:N/S:U/C:N/I:H/A:H
NVD	3.1	6.0	CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:H
NVD	2.0	3.6	AV:L/AC:L/Au:N/C:N/I:P/A:P

Affected products

The Grub2 Project grub2

Classification

Weakness

CWE-190 Integer Overflow or Wraparound
CWE-122 Heap-based Buffer Overflow

References

usn.ubuntu.com /4432-1/
vendor-advisory, third-party-advisory
lists.opensuse.org /opensuse-security-announce/2020-08/msg00017.html
vendor-advisory, mailing-list, third-party-advisory
lists.opensuse.org /opensuse-security-announce/2020-08/msg00016.html
vendor-advisory, mailing-list, third-party-advisory
security.gentoo.org /glsa/202104-05
vendor-advisory, third-party-advisory
bugzilla.redhat.com /show_bug.cgi?id=CVE-2020-14311
issue-tracking, third-party-advisory
openwall.com /lists/oss-security/2021/09/17/2
mailing-list, third-party-advisory
openwall.com /lists/oss-security/2021/09/17/4
mailing-list, third-party-advisory
openwall.com /lists/oss-security/2021/09/21/1
mailing-list, third-party-advisory

Sources

CVE List CVE-2020-14311
NVD CVE-2020-14311

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary