Security readout for executives and security teams
Plain-English summary
CVE-2021-40753 is a high-severity Adobe After Effects flaw where opening a malicious SVG file can corrupt memory and let attacker-controlled code run as the logged-in user. The business risk is concentrated on creative workstations that receive untrusted media assets.
Executive priority
Prioritize remediation for creative teams that exchange outside media assets. This is not remotely exploitable without user interaction, but successful exploitation can run code on employee workstations and affect sensitive project files or credentials accessible to that user.
Technical view
Adobe After Effects 18.4.1 and earlier are affected by memory corruption in SVG file handling. The CVSS 3.0 score is 7.8 with local attack vector and required user interaction. Successful exploitation can affect confidentiality, integrity, and availability in the current user context.
Likely exposure
Exposure is likely limited to endpoints running affected Adobe After Effects versions, especially designers, editors, or marketing teams opening SVG or project assets from external sources. Servers are not the primary concern based on the provided sources.
Exploitation context
The provided data does not show known active exploitation; KEV is false. Exploitation requires a user to open a specially crafted SVG file, so phishing, shared asset repositories, or third-party creative submissions are plausible delivery paths.
Researcher notes
The available record identifies CWE-788 and memory corruption during malicious SVG parsing. The bundle does not include exploit maturity, proof-of-concept status, or exact fixed build details beyond the Adobe advisory reference, so validation should focus on version exposure and vendor bulletin confirmation.
Mitigation direction
- Apply Adobe’s APSB21-79 guidance for After Effects updates.
- Confirm After Effects is newer than affected 18.4.1-and-earlier builds.
- Restrict opening SVG files from untrusted sources until patched.
- Use least-privilege accounts for creative workstation users.
- Review vendor guidance before relying on compensating controls.
Validation and detection
- Inventory Adobe After Effects versions across endpoints.
- Identify users or teams handling external SVG assets.
- Confirm patch status against Adobe APSB21-79.
- Check whether endpoint controls inspect downloaded or emailed SVG files.
- Review recent security alerts involving After Effects process activity.
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-2021-40753 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 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/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:3.0/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H1.85.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
7.8HighVector: CVSS:3.0/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.