← Vulnerability feed

Vulnerability record · CVE-2020-27749 · published 3 March 2021

CVE-2020-27749: Gnu grub2 stack-based buffer overflow vulnerability

Gnu · Grub2

A flaw was found in grub2 in versions prior to 2.06. Variable names present are expanded in the supplied command line into their corresponding variable contents, using a 1kB stack buffer for temporary storage, without sufficient bounds checking. If the function is called with a command line that references a variable with a sufficiently large payload, it is possible to overflow the stack buffer, corrupt the stack frame and control execution which could also circumvent Secure Boot protections. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

6.7 CVSS 3.1 Medium EPSS 0.57% · top 52.1% CWE-121 · Stack-based buffer overflowCWE-787 · Out-of-bounds write
6.7CVSS 3.1 base score, v2 7.2
0.57%EPSS exploitation probability, 30 days
NoNot in CISA KEV
8Affected product versions listed by NVD
8References
17 Jun 2026Last modified by NVD

Description

A flaw was found in grub2 in versions prior to 2.06. Variable names present are expanded in the supplied command line into their corresponding variable contents, using a 1kB stack buffer for temporary storage, without sufficient bounds checking. If the function is called with a command line that references a variable with a sufficiently large payload, it is possible to overflow the stack buffer, corrupt the stack frame and control execution which could also circumvent Secure Boot protections. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Affected products

8 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://bugzilla.redhat.com/show_bug.cgi?id=1899966 Issue TrackingPatchThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH
https://security.gentoo.org/glsa/202104-05 Third Party Advisory
https://security.netapp.com/advisory/ntap-20220325-0001/ Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1899966 Issue TrackingPatchThird Party Advisory
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZWZ36QK4IKU6MWDWNOOWKPH
https://security.gentoo.org/glsa/202104-05 Third Party Advisory
https://security.netapp.com/advisory/ntap-20220325-0001/ Third Party Advisory

Track CVE-2020-27749 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

10.0CVE-2021-44228Apache Log4j2 JNDI lookup remote code executionApache Log4j2 versions 2.0-beta9 through 2.15.0 (excluding 2.12.2, 2.12.3, and 2.3.1) do not protect against attacker-controlled LDAP and other JNDI …KEVEPSS 100%analysed10.0CVE-2015-3306ProFTPD mod_copy arbitrary file read and writeThe mod_copy module in ProFTPD 1.3.5 fails to restrict the SITE CPFR and SITE CPTO commands, letting remote attackers copy arbitrary files on the ser…KEVEPSS 99%analysed9.8CVE-2024-4577PHP-CGI on Windows argument injection leads to remote code executionPHP-CGI on Windows can misinterpret characters in the command line passed to Win32 API functions when certain code pages are configured, due to Windo…KEVEPSS 100%analysed9.8CVE-2021-44026Roundcube Webmail SQL injection via search parametersRoundcube Webmail before 1.3.17 and 1.4.x before 1.4.12 is prone to SQL injection through the search or search_params input. The flaw is remotely rea…KEVEPSS 70%analysed9.8CVE-2021-42013Apache HTTP Server path traversal and RCE via incomplete fixThe fix for CVE-2021-41773 in Apache HTTP Server 2.4.50 was insufficient, leaving a path traversal flaw that lets attackers map URLs to files outside…KEVEPSS 100%analysed9.8CVE-2021-41773Apache HTTP Server 2.4.49 path traversal and RCEA path normalization flaw introduced in Apache HTTP Server 2.4.49 lets attackers map URLs to files outside directories configured by Alias-like direc…KEVEPSS 100%analysed9.8CVE-2021-1870Apple WebKit logic flaw allows remote code executionA logic issue in Apple's WebKit was addressed with improved restrictions, affecting macOS Big Sur, Catalina, Mojave, iOS and iPadOS, plus WebKitGTK a…KEVEPSS 7.7%analysed9.8CVE-2021-1871Apple WebKit logic flaw allows remote code executionA logic issue in Apple's WebKit was addressed with improved restrictions. It affects macOS Big Sur, Catalina, Mojave, iOS and iPadOS, and a remote at…KEVEPSS 7.0%analysed

Source: NIST National Vulnerability Database (record CVE-2020-27749), CISA KEV, FIRST EPSS (scores of 2026-11-14). This page is refreshed as NVD updates the record.