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CVE Record

CVE-2021-39170: Improper Encoding or Escaping of Output in Asset Metadata Component

Pimcore is an open source data & experience management platform. Prior to version 10.1.2, an authenticated user could add XSS code as a value of custom metadata on assets. There is a patch for this issue in Pimcore version 10.1.2. As a workaround, users may apply the patch manually.

HighCVSS 8Not KEV-listedUpdated
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Glexia's TakeAutomated analysishigh

Security readout for executives and security teams

Plain-English summary

Pimcore before 10.1.2 allowed an authenticated user to store unsafe script content in asset custom metadata. When another user views that metadata, the content could run in their browser, risking account actions or data exposure inside Pimcore. The vendor lists a patch in version 10.1.2.

Executive priority

Treat as a high-priority application security fix for affected Pimcore environments. It requires authentication, but the business risk is meaningful where editors or partners can modify asset metadata viewed by privileged users.

Technical view

This is a CWE-116 output encoding issue in Pimcore asset metadata rendering. The CVSS 3.1 vector is AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H, score 8.0. Exploitation requires an authenticated user who can edit asset custom metadata and another user interaction to render it.

Likely exposure

Exposure is limited to Pimcore deployments below 10.1.2 where authenticated users can set asset custom metadata. Risk is higher in environments with many content editors, shared authoring workflows, or privileged users reviewing untrusted assets.

Exploitation context

The provided sources do not show CISA KEV listing or active exploitation. The issue is still serious because stored XSS can persist in asset metadata and affect later viewers, including higher-privileged Pimcore users.

Researcher notes

Evidence supports affected Pimcore versions below 10.1.2 and a patch in 10.1.2. No exploit status is established by the provided bundle. Avoid assuming impact outside Pimcore asset custom metadata without additional vendor evidence.

Mitigation direction

  • Upgrade Pimcore to version 10.1.2 or later.
  • If upgrade is delayed, apply the vendor patch manually.
  • Restrict asset metadata editing to trusted roles until fixed.
  • Review vendor advisory before production remediation.
  • Audit existing asset metadata for unexpected script-like content.

Validation and detection

  • Confirm the running Pimcore version is 10.1.2 or later.
  • Verify the vendor patch is present in deployed code.
  • Review who can edit asset custom metadata.
  • Check existing custom metadata for suspicious active content.
  • Test metadata display paths for safe output encoding.
Prepared
Confidence
high
Sources
6

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

Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.

cwe · medium confidence lookup

CWE-116: User-session and phishing behavior lookup

Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.

Open ATT&CK lookup
cve · low confidence lookup

CVE-2021-39170 mapping review

Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.

Open ATT&CK lookup
Vulnerability profileCVE Program record
Severity
High
CVSS
8 (3.1)
Known Exploited
No
Published

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

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
5Source 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
8CVSS 3.1HighCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H2.15.9Primary CVE score

Vulnerability scoring details

Base CVSS 3.1 score

8High
CVSS 3.1 vector shape for CVE-2021-39170Attack VectorAttack ComplexityPrivileges RequiredUser InteractionScopeConfidentiality ImpactIntegrity ImpactAvailability Impact

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

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
pimcorepimcore< 10.1.2Listed
Weakness

CWE details

CWE-116

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

CWE-116 · source CWE mapping

Improper Encoding or Escaping of Output

Improper Encoding or Escaping of Output represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.

Open CWE intelligenceSame-CWE CVEs