Security readout for executives and security teams
Plain-English summary
This issue can make Adobe InCopy crash when a user opens a maliciously crafted file. It does not indicate data theft or code execution in the provided sources, but it can disrupt work for affected users. The practical risk depends on whether staff use Adobe InCopy 16.4 or earlier and open files from untrusted sources.
Executive priority
Treat this as a moderate workstation availability risk, not an enterprise-critical emergency based on the provided evidence. Prioritize teams that use InCopy and handle outside files, then verify vendor remediation status.
Technical view
CVE-2021-43016 is a CWE-476 null pointer dereference in Adobe InCopy 16.4 and earlier during crafted file parsing. The CVSS 3.1 score is 5.5 with local attack vector, no privileges required, required user interaction, unchanged scope, and high availability impact only.
Likely exposure
Exposure is likely limited to endpoints running Adobe InCopy 16.4 or earlier, especially publishing, marketing, design, or editorial teams that receive InCopy-related files from external parties.
Exploitation context
The source bundle says exploitation requires user interaction: a victim must open a malicious file. CISA KEV status is false, and the provided sources do not state active exploitation in the wild.
Researcher notes
Evidence supports denial of service only, with no confidentiality or integrity impact in CVSS. The bundle does not provide exploit reports, proof-of-concept status, or fixed-version details, so remediation should be aligned with Adobe APSB21-110.
Mitigation direction
- Inventory Adobe InCopy installations and versions across user endpoints.
- Review Adobe APSB21-110 for vendor-approved update or remediation guidance.
- Update or remove Adobe InCopy 16.4 and earlier where practical.
- Limit opening InCopy files from unknown or untrusted sources.
- Use endpoint controls to quarantine suspicious document attachments.
Validation and detection
- Confirm whether any endpoints run Adobe InCopy 16.4 or earlier.
- Check patch management records against Adobe APSB21-110 guidance.
- Review recent security alerts involving suspicious InCopy or design files.
- Validate user awareness controls for externally supplied creative files.
- Confirm affected endpoints have current endpoint protection enabled.
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.
CWE-476: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. 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 lookupCVE-2021-43016 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
- Medium
- CVSS
- 5.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
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 vector scores
1 official scoreWe 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.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H1.83.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
5.5MediumVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://helpx.adobe.com/security/products/incopy/apsb21-110.htmlCVE 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.
NULL Pointer Dereference
NULL Pointer Dereference represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.