Evidence dossier

CVE-2021-3156

CVE-2021-3156

77.9–94.4Priority evidence range

As known Jul 19, 2026, 5:00 AM UTCgen-56ccdaf9

Normalized restatement

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.

State: PUBLISHED
Published: Jan 26, 2021
Updated: Oct 21, 2025
Evidence coverage: 85%

CISA KEVCatalog member

Apply updates per vendor instructions.

FIRST EPSS99.30%

2026-07-18 · v2026.06.15 · percentile 99.9%

Source stateNo scored conflict

Distinct CVSS assessments remain side by side; none are averaged.

Source comparison

Who said what

CISA-ADPindependent enrichment

container

CISA ADP Vulnrichment

Jul 19, 2026Original evidence ↗

CVEderivative copy

container

CVE Program Container

Jul 19, 2026Original evidence ↗

mitreoriginal assertion

container

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.

Jul 19, 2026Original evidence ↗

CISA KEVoriginal assertion

observed_exploitation

Sudo Heap-Based Buffer Overflow Vulnerability

Jul 19, 2026Original evidence ↗

FIRST EPSSoriginal assertion

model_probability

Probability 0.992950000000; percentile 0.999340000000

Jul 19, 2026Original evidence ↗

Applicability

Cited product scope

Trace impact →

n/an/a

[{"status": "affected", "version": "n/a"}]unknown

Unknown vendorUnknown product

cpe:2.3:a:beyondtrust:privilege_management_for_mac:*:*:*:*:*:*:*:*; end excluding 21.1.1supported

Unknown vendorUnknown product

cpe:2.3:a:beyondtrust:privilege_management_for_unix\/linux:*:*:*:*:basic:*:*:*; end excluding 10.3.2-10supported

Unknown vendorUnknown product

cpe:2.3:a:mcafee:web_gateway:10.0.4:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:mcafee:web_gateway:8.2.17:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:mcafee:web_gateway:9.2.8:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:netapp:active_iq_unified_manager:-:*:*:*:*:vmware_vsphere:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:netapp:cloud_backup:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:netapp:oncommand_unified_manager_core_package:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:netapp:ontap_select_deploy_administration_utility:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:netapp:ontap_tools:9:*:*:*:*:vmware_vsphere:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:oracle:communications_performance_intelligence_center:*:*:*:*:*:*:*:*; start including 10.3.0.0.0; end including 10.3.0.2.1

supported

Unknown vendorUnknown product

cpe:2.3:a:oracle:communications_performance_intelligence_center:*:*:*:*:*:*:*:*; start including 10.4.0.1.0; end including 10.4.0.3.1

supported

Unknown vendorUnknown product

cpe:2.3:a:oracle:tekelec_platform_distribution:*:*:*:*:*:*:*:*; start including 7.4.0; end including 7.7.1supported

Unknown vendorUnknown product

cpe:2.3:a:sudo_project:sudo:*:*:*:*:*:*:*:*; start including 1.8.2; end excluding 1.8.32supported

Unknown vendorUnknown product

cpe:2.3:a:sudo_project:sudo:*:*:*:*:*:*:*:*; start including 1.9.0; end excluding 1.9.5supported

Unknown vendorUnknown product

cpe:2.3:a:sudo_project:sudo:1.9.5:-:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:sudo_project:sudo:1.9.5:patch1:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:a:synology:diskstation_manager_unified_controller:3.0:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:h:oracle:micros_compact_workstation_3:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:oracle:micros_es400:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:oracle:micros_kitchen_display_system:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:oracle:micros_workstation_5a:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:oracle:micros_workstation_6:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:synology:skynas:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:h:synology:vs960hd:-:*:*:*:*:*:*:*constrained

Unknown vendorUnknown product

cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:fedoraproject:fedora:32:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:fedoraproject:fedora:33:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:oracle:micros_compact_workstation_3_firmware:310:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:oracle:micros_es400_firmware:*:*:*:*:*:*:*:*; start including 400; end including 410supported

Unknown vendorUnknown product

cpe:2.3:o:oracle:micros_kitchen_display_system_firmware:210:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:oracle:micros_workstation_5a_firmware:5a:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:oracle:micros_workstation_6_firmware:*:*:*:*:*:*:*:*; start including 610; end including 655supported

Unknown vendorUnknown product

cpe:2.3:o:synology:diskstation_manager:6.2:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:synology:skynas_firmware:-:*:*:*:*:*:*:*supported

Unknown vendorUnknown product

cpe:2.3:o:synology:vs960hd_firmware:-:*:*:*:*:*:*:*supported

Assessments

CVSS by origin

7.8

nvd@nist.govCVSS 3.1 · role PrimaryCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

7.2

nvd@nist.govCVSS 2.0 · role PrimaryAV:L/AC:L/Au:N/C:C/I:C/A:C

7.8

134c704f-9b21-4f2e-91b3-4a467353bcc0CVSS 3.1 · role SecondaryCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

7.8

CISA-ADPCVSS 3.1 · role unknownCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Limitations and unknowns

KEV membership is authoritative for the catalog, not proof of exposure in any environment.
EPSS is a dated model probability and not an individual-environment prediction.
Affected or fixed status applies only to the exact cited product and version scope; unresolved scope remains unknown.
NVD-carried upstream facts remain derivative and are not independent corroboration.
Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
Factor D is unknown in Public Core because no accepted canonical mapping-obligation ledger is present.
Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.