Security readout for executives and security teams
Plain-English summary
A malicious InDesign file could cause vulnerable Adobe InDesign versions to run attacker-controlled code when a user opens it. This is a workstation compromise risk, mainly for design, marketing, publishing, and creative teams that exchange external files.
Executive priority
Prioritize remediation for creative and publishing workstations because successful exploitation can give an attacker code execution with the user’s access. The urgency is high, but the supplied evidence does not show active exploitation.
Technical view
CVE-2021-42731 is a CWE-120 buffer overflow in Adobe InDesign 16.4 and earlier during crafted file parsing. CVSS 3.1 is 7.8. Exploitation requires local file opening by a user, needs no privileges, and could execute code as the current user.
Likely exposure
Exposure is likely where Adobe InDesign 16.4 or earlier remains installed on endpoints and users receive files from external parties. The provided sources do not indicate server-side exposure or affected Adobe products beyond InDesign.
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 support a claim of active exploitation.
Researcher notes
The public data identifies affected versions as 16.4 and earlier and describes arbitrary code execution through crafted file parsing. Fixed-version details are not included in the provided bundle, so researchers should rely on Adobe APSB21-107 for exact remediation mapping.
Mitigation direction
- Identify endpoints running Adobe InDesign 16.4 or earlier.
- Update Adobe InDesign according to Adobe APSB21-107 guidance.
- Limit opening InDesign files from unknown or untrusted sources.
- Use endpoint controls to inspect or quarantine suspicious design files.
- Review vendor guidance if patch status is unclear.
Validation and detection
- Confirm installed InDesign versions against Adobe APSB21-107.
- Verify vulnerable versions are removed or updated on managed endpoints.
- Check endpoint logs for suspicious activity after opening design files.
- Review mail and file-transfer paths used by creative teams.
- Confirm users handling external files received phishing-risk guidance.
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-120: 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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-42731 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
- High
- CVSS
- 7.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/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:H/I:H/A:H1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.8HighVector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://helpx.adobe.com/security/products/indesign/apsb21-107.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.
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
Buffer Copy without Checking Size of Input ('Classic Buffer Overflow') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.