Security readout for executives and security teams
Plain-English summary
CVE-2021-40760 affects Adobe After Effects 18.4.1 and earlier. A user opening a malicious .m4a audio file could allow attacker code to run with that user’s permissions. This is a workstation-focused risk, mainly relevant where After Effects users handle files from external or untrusted sources.
Executive priority
Treat this as a high-priority workstation remediation for teams using After Effects. It is not described as remotely exploitable without user action, but successful exploitation could compromise sensitive files and workstation integrity.
Technical view
The issue is a memory corruption vulnerability in After Effects .m4a parsing, mapped to CWE-788. CVSS 3.1 is 7.8 with local attack vector, low complexity, no privileges required, required user interaction, unchanged scope, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is limited to endpoints running Adobe After Effects 18.4.1 or earlier, especially creative, marketing, media, and production teams that open externally supplied audio or project assets.
Exploitation context
The provided sources do not show CISA KEV listing or confirmed active exploitation. Exploitation requires convincing a user to open a specially crafted .m4a file in an affected After Effects installation.
Researcher notes
Evidence is limited to the CVE record and Adobe advisory reference. The sources identify affected versions, impact, required user interaction, CVSS, and CWE, but do not provide exploit-in-the-wild evidence in the supplied bundle.
Mitigation direction
- Inventory Adobe After Effects installations and identify versions 18.4.1 or earlier.
- Review Adobe APSB21-79 for the vendor-supported fixed version and update path.
- Restrict handling of untrusted .m4a files on systems with affected After Effects versions.
- Use least-privilege user accounts for creative workstations where practical.
- Apply endpoint controls for suspicious files received by email, chat, or file-sharing workflows.
Validation and detection
- Confirm installed After Effects versions across managed endpoints.
- Check whether any systems remain on 18.4.1 or earlier.
- Verify remediation against Adobe APSB21-79 guidance, not assumptions.
- Review file-ingress workflows for externally supplied .m4a assets.
- Monitor endpoint detections involving After Effects opening unexpected media files.
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-788: 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-2021-40760 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/after_effects/apsb21-79.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.
Access of Memory Location After End of Buffer
Access of Memory Location After End of Buffer represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.