CVE-2021-39879

Two-factor authentication disablement via missing authentication

Published Oct 4, 2021 · Updated Aug 4, 2024

Missing authentication in GitLab 7.11.0 through 14.1.6 allows attackers with a victim session to disable two-factor authentication. The published record does not identify the request handler or explain which authentication operation is omitted when the second factor is disabled. Exploitation requires access to an active victim session and user interaction; the bounded effect is removal of that account's second factor.

CVSS severity2.2
Low
EPSS probability0.41%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Missing authentication in GitLab 7.11.0 through 14.1.6 allows attackers with a victim session to disable two-factor authentication. The published record does not identify the request handler or explain which authentication operation is omitted when the second factor is disabled. Exploitation requires access to an active victim session and user interaction; the bounded effect is removal of that account's second factor.

The record

CVE
CVE-2021-39879
Published
Oct 4, 2021
Updated
Aug 4, 2024
Vendor
GitLab
Product
GitLab
Classifications
CWE-306, T1562.001
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Oct 4, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=>=7.11.0, <14.1.7

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

GitLab · GitLabversion=>=7.11.0, <14.1.7

Published CVSS scores

4.0NVDAV:N/AC:L/Au:S/C:N/I:P/A:N
3.5NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
2.2GitLab Inc.CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-306Missing Authentication for Critical Function
T1562.001Impair Defenses: Disable or Modify Tools

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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