CVE-2021-3156

Published Jan 26, 2021

Last updated 4 months ago

Exploit knownCVSS high 7.8

Overview

Description
Sudo before 1.9.5p2 contains an off-by-one error that can result in a heap-based buffer overflow, which allows privilege escalation to root via "sudoedit -s" and a command-line argument that ends with a single backslash character.
Source
cve@mitre.org
NVD status
Analyzed
Products
sudo, fedora, debian_linux, active_iq_unified_manager, cloud_backup, hci_management_node, oncommand_unified_manager_core_package, ontap_select_deploy_administration_utility, ontap_tools, solidfire, web_gateway, diskstation_manager_unified_controller, diskstation_manager, skynas_firmware, vs960hd_firmware, privilege_management_for_mac, privilege_management_for_unix\/linux, micros_compact_workstation_3_firmware, micros_es400_firmware, micros_kitchen_display_system_firmware, micros_workstation_5a_firmware, micros_workstation_6_firmware, communications_performance_intelligence_center, tekelec_platform_distribution

Risk scores

CVSS 3.1

Type
Primary
Base score
7.8
Impact score
5.9
Exploitability score
1.8
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Severity
HIGH

CVSS 2.0

Type
Primary
Base score
7.2
Impact score
10
Exploitability score
3.9
Vector string
AV:L/AC:L/Au:N/C:C/I:C/A:C

Known exploits

Data from CISA

Vulnerability name
Sudo Heap-Based Buffer Overflow Vulnerability
Exploit added on
Apr 6, 2022
Exploit action due
Apr 27, 2022
Required action
Apply updates per vendor instructions.

Weaknesses

nvd@nist.gov
CWE-193
134c704f-9b21-4f2e-91b3-4a467353bcc0
CWE-193

Social media

Hype score
Not currently trending

  1. CVE-2021-3156 Sudo before 1.9.5p2 contains an off-by-one error that can result in a heap-based buffer overflow, which allows privilege escalation to root via "sudoedit -s".. Github link: https://t.co/DbwhNy47Fe

    @PoC_in_Github

    19 Jul 2025

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Configurations

Related CVEs

  1. MUNGE is an authentication service for creating and validating user credentials. From 0.5 to 0.5.17, local attacker can exploit a buffer overflow vulnerability in munged (the MUNGE authentication daemon) to leak cryptographic key material from process memory. With the leaked key material, the attacker could forge arbitrary MUNGE credentials to impersonate any user (including root) to services that rely on MUNGE for authentication. The vulnerability allows a buffer overflow by sending a crafted message with an oversized address length field, corrupting munged's internal state and enabling extraction of the MAC subkey used for credential verification. This vulnerability is fixed in 0.5.18.•CVE-2026-25506
  2. Fast DDS is a C++ implementation of the DDS (Data Distribution Service) standard of the OMG (Object Management Group ). Prior to versions 3.4.1, 3.3.1, and 2.6.11, when the security mode is enabled, modifying the DATA Submessage within an SPDP packet sent by a publisher causes an Out-Of-Memory (OOM) condition, resulting in remote termination of Fast-DDS. If t he fields of `PID_IDENTITY_TOKEN` or `PID_PERMISSIONS_TOKEN` in the DATA Submessage are tampered with — specifically by ta mpering with the the `vecsize` value read by `readOctetVector` — a 32-bit integer overflow can occur, causing `std::vector ::resize` to request an attacker-controlled size and quickly trigger OOM and remote process termination. Versions 3.4.1, 3 .3.1, and 2.6.11 patch the issue.•CVE-2025-64098
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  4. Fast DDS is a C++ implementation of the DDS (Data Distribution Service) standard of the OMG (Object Management Group ). Prior to versions 3.4.1, 3.3.1, and 2.6.11, when the security mode is enabled, modifying the DATA Submessage within an SPDP packet sent by a publisher causes a heap buffer overflow, resulting in remote termination of Fast-DDS. If the fields of `PID_IDENTITY_TOKEN` or `PID_PERMISSIONS_TOKEN` in the DATA Submessage are tampered with — specially `readOctetVector` reads an unchecked `vecsize` that is propagated unchanged into `readData` as the `length` parameter — the attacker-contro lled `vecsize` can trigger a 32-bit integer overflow during the `length` calculation. That overflow can cause large alloca tion attempt that quickly leads to OOM, enabling a remotely-triggerable denial-of-service and remote process termination. Versions 3.4.1, 3.3.1, and 2.6.11 patch the issue.•CVE-2025-62602
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References

Sources include official advisories and independent security research.