Security readout for executives and security teams
Plain-English summary
This vulnerability affects Adobe After Effects when it processes a malicious SGI image file. If a user opens such a file, After Effects could run attacker-controlled code with that user’s permissions. The practical risk is highest for creative or media teams that receive project assets from external parties.
Executive priority
Treat this as a high-priority workstation risk for creative teams, not an internet-wide emergency. Prioritize patch verification and controls around externally supplied media files, because compromise could execute code under the affected user account.
Technical view
CVE-2021-40755 is a memory corruption issue in Adobe After Effects 18.4.1 and earlier, tied to insecure SGI file handling in DoReadContinue. It is classified as CWE-788 and scored CVSS 7.8. Exploitation requires local file interaction by a user and may lead to arbitrary code execution in the current user context.
Likely exposure
Exposure is likely limited to endpoints with Adobe After Effects 18.4.1 or earlier, especially systems that open SGI files or ingest third-party media assets. Server exposure is not indicated by the sources.
Exploitation context
The source bundle does not show CISA KEV listing or active exploitation evidence. Exploitation requires user interaction, likely through opening a crafted SGI file in After Effects. No exploit status beyond potential arbitrary code execution is supported here.
Researcher notes
The strongest evidence is the CVE description, CVSS vector, CWE classification, and Adobe bulletin reference. The provided affected-version data is sparse, but the description names After Effects 18.4.1 and earlier. No exploit-in-the-wild evidence is included.
Mitigation direction
- Review Adobe APSB21-79 for the vendor-approved update or remediation path.
- Inventory and prioritize After Effects 18.4.1 and earlier installations.
- Limit opening SGI files from untrusted or external sources until remediated.
- Use endpoint controls to reduce impact from code execution in user context.
Validation and detection
- Confirm installed Adobe After Effects versions across managed endpoints.
- Flag systems running After Effects 18.4.1 or earlier for remediation tracking.
- Review creative asset workflows for SGI files from external sources.
- Check Adobe APSB21-79 for fixed-version guidance before closing findings.
- Document that KEV evidence was not present in the provided bundle.
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-2021-40755 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.