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CVE Record

CVE-2021-22220: An issue has been discovered in GitLab affecting all versions starting with 13.10.

An issue has been discovered in GitLab affecting all versions starting with 13.10. GitLab was vulnerable to a stored XSS in blob viewer of notebooks.

MediumCVSS 6.1Not KEV-listedUpdated
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Glexia's TakeAutomated analysismoderate

Security readout for executives and security teams

Plain-English summary

GitLab versions in the listed 13.10, 13.11, and 13.12 ranges could store malicious script content in notebook blob views. A victim would need to view the affected content, but successful exploitation could expose browser-session data or let the attacker perform limited actions in the victim’s context.

Executive priority

Treat as a near-term patching item, not an emergency remote-code-execution event. Prioritize internet-facing or collaboration-heavy GitLab instances where untrusted notebook content may be viewed by staff.

Technical view

CVE-2021-22220 is a stored XSS in GitLab’s notebook blob viewer. CVSS 3.1 is 6.1: network reachable, low complexity, no privileges required, user interaction required, changed scope, low confidentiality and integrity impact, no availability impact. Affected ranges are 13.10 before 13.10.5, 13.11 before 13.11.5, and 13.12 before 13.12.2.

Likely exposure

Exposure is likely where self-managed GitLab instances run the affected 13.10 through 13.12 versions and users can view notebook files from untrusted or less-trusted sources.

Exploitation context

The source bundle does not show CISA KEV listing or active exploitation evidence. Risk depends on a victim viewing stored notebook content in GitLab’s blob viewer, which makes phishing-like or collaborative-repository scenarios more relevant than unauthenticated server compromise.

Researcher notes

Key constraints are user interaction and stored content rendering. The bundle provides no CWE and no active exploitation signal. Validation should focus on version exposure, notebook viewer reachability, and contributor trust boundaries without attempting weaponized XSS reproduction.

Mitigation direction

  • Upgrade affected GitLab 13.10 deployments to 13.10.5 or later supported versions.
  • Upgrade affected GitLab 13.11 deployments to 13.11.5 or later supported versions.
  • Upgrade affected GitLab 13.12 deployments to 13.12.2 or later supported versions.
  • Check current GitLab vendor guidance before applying compensating controls.
  • Limit viewing of notebook content from untrusted projects until patched.

Validation and detection

  • Inventory self-managed GitLab versions and compare against the affected version ranges.
  • Confirm patched instances are outside 13.10 <13.10.5, 13.11 <13.11.5, and 13.12 <13.12.2.
  • Identify repositories containing notebook files and review whether untrusted users can contribute them.
  • Review security tooling results for CVE-2021-22220 after upgrade.
  • Confirm no exception process leaves affected GitLab instances internet-accessible.
Prepared
Confidence
high
Sources
5

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

Conservative CVE-to-ATT&CK context

These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.

ATT&CK lookup starting points

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CVE-2021-22220 mapping review

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Vulnerability profileCVE Program record
Severity
Medium
CVSS
6.1 (3.1)
Known Exploited
No
Published

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

1CVSS vectors
0Timeline events
0ADP providers
4Source links

CVSS vector scores

1 official score

We collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.

ScoreVersionSeverityVectorExploitImpactSource
6.1CVSS 3.1MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N2.82.7Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

6.1Medium
CVSS 3.1 vector shape for CVE-2021-22220Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Attack Vector
NetworkAdjacentLocalPhysical
Attack Complexity
LowHigh
Privileges Required
NoneLowHigh
User Interaction
NoneRequired
Scope
ChangedUnchanged
Confidentiality Impact
HighLowNone
Integrity Impact
HighLowNone
Availability Impact
HighLowNone

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
GitLabGitLab>=13.12, <13.12.2, >=13.11, <13.11.5, >=13.10, <13.10.5Listed
Weakness

CWE details

No CWE listed

CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.