Security readout for executives and security teams
Plain-English summary
A malicious M4A audio file can trigger memory corruption in Adobe Media Encoder 15.4 and earlier. If a user opens the file, code could run with that user’s permissions. This is primarily an endpoint and creative-workstation risk, not a directly internet-exposed server issue.
Executive priority
Treat as high priority for creative and media-handling teams. The issue can lead to code execution, but it needs user interaction and is not listed as known exploited in the provided sources.
Technical view
CVE-2021-46817 is a CWE-787 out-of-bounds write/memory corruption flaw in Adobe Media Encoder. The CVSS 3.1 score is 7.8, with low attack complexity, no privileges required, and required user interaction. Successful exploitation may allow arbitrary code execution as the current user.
Likely exposure
Organizations are exposed where Adobe Media Encoder 15.4 or earlier is installed, especially on systems handling media from external parties. Exposure depends on users opening malicious M4A files. The bundle does not identify other Adobe products as affected.
Exploitation context
The source bundle does not report active exploitation, and KEV is false. Exploitation requires victim interaction: opening a malicious M4A file. The sources do not provide exploit maturity, public proof-of-concept status, or observed campaign evidence.
Researcher notes
The bundle supports Adobe Media Encoder 15.4 and earlier, CWE-787, CVSS 7.8, and user-assisted arbitrary code execution through malicious M4A parsing. Patch specifics, exploit availability, and telemetry are not included, so validation should stay anchored to Adobe APSB21-70 and local asset data.
Mitigation direction
- Inventory endpoints for Adobe Media Encoder 15.4 and earlier.
- Apply Adobe guidance from APSB21-70; do not infer an unlisted fixed version.
- Restrict opening unsolicited M4A files until affected systems are remediated.
- Prioritize users who process external media or client-submitted audio.
- Use endpoint controls to reduce impact from user-context code execution.
Validation and detection
- Confirm installed Adobe Media Encoder versions across managed endpoints.
- Check whether any systems remain on version 15.4 or earlier.
- Verify remediation against Adobe APSB21-70 guidance.
- Review recent handling of untrusted M4A files by high-risk users.
- Confirm endpoint detection coverage on creative workstations.
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
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CWE-787: Exact CWE lookup
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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-2021-46817 mapping review
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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/media-encoder/apsb21-70.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.
Out-of-bounds Write
Out-of-bounds Write represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.