CVE-2021-22210Network attack vector

Service interruption via unbounded branch API results

Published May 6, 2021 · Updated Aug 3, 2024

Resource exhaustion in affected GitLab CE/EE 13.x releases allows remote attackers to interrupt service through the repository branches API. The repository branches endpoint fails to apply a result-limiting query parameter before assembling its response, so one request returns a considerable branch set. The request is unauthenticated for public repositories, and the documented consequence is availability loss rather than data access or modification.

CVSS severity5.3
Medium
EPSS probability1.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Resource exhaustion in affected GitLab CE/EE 13.x releases allows remote attackers to interrupt service through the repository branches API. The repository branches endpoint fails to apply a result-limiting query parameter before assembling its response, so one request returns a considerable branch set. The request is unauthenticated for public repositories, and the documented consequence is availability loss rather than data access or modification.

The record

CVE
CVE-2021-22210
Published
May 6, 2021
Updated
Aug 3, 2024
Vendor
GitLab
Product
GitLab
Classifications
CWE-770, T1499.003
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. May 6, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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=>=13.10, <13.10.4
  2. Affected versionversion=>=13.11, <13.11.2
  3. Affected versionversion=>=13.2, <13.9.7

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

GitLab · GitLabversion=>=13.10, <13.10.4; version=>=13.11, <13.11.2; version=>=13.2, <13.9.7

Published CVSS scores

5.0NIST NVDAV:N/AC:L/Au:N/C:N/I:N/A:P
5.3GitLab Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

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

Weakness, pattern, technique

CWE-770Allocation of Resources Without Limits or Throttling
T1499.003Application Exhaustion Flood

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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