Security readout for executives and security teams
Plain-English summary
CVE-2021-39248 is a cross-site scripting issue in Open edX discussion handling. A crafted LaTeX discussion post could run script in another user’s browser. The sources do not provide CVSS, confirmed exploitation, or a complete affected-version matrix beyond Open edX through Lilac.1.
Executive priority
Treat this as a moderate web-application risk if Open edX discussions are public or widely used. Prioritize confirming exposure and applying vendor-supported fixes, but do not escalate as an active-exploitation emergency based on the supplied evidence.
Technical view
The CVE describes XSS in common/static/common/js/discussion/utils.js, triggered by crafted LaTeX content inside an Open edX discussion. The only linked remediation evidence is an edx-platform pull request. No CWE, CVSS vector, CPE, or exploit-in-the-wild evidence is provided in the source bundle.
Likely exposure
Exposure is most likely in Open edX deployments through Lilac.1 that enable discussions and render user-submitted LaTeX content. The source bundle does not identify cloud services, forks, plugins, or later fixed releases.
Exploitation context
The source bundle supports potential stored or reflected browser-side impact through malicious discussion content, but does not document active exploitation. CISA KEV is false, and no cited source claims exploitation in the wild.
Researcher notes
The record is sparse: no CVSS, CWE, CPE, or detailed affected range is present. Analysis should center on the Open edX discussion LaTeX rendering path and the referenced edx-platform PR, without assuming exploit availability or fixed versions not shown here.
Mitigation direction
- Check Open edX vendor guidance for CVE-2021-39248.
- Review edx-platform pull request 28379 for the applicable fix.
- Upgrade or patch only according to confirmed Open edX guidance.
- Restrict untrusted discussion posting if patch timing is uncertain.
Validation and detection
- Inventory Open edX deployments and confirm Lilac.1 or earlier exposure.
- Verify whether discussion features and LaTeX rendering are enabled.
- Compare deployed discussion utils.js behavior with vendor fix references.
- Review discussion moderation logs for suspicious LaTeX content.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
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.
CVE-2021-39248 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/edx/edx-platform/pull/28379CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.