Security readout for executives and security teams
Plain-English summary
This flaw affects Adobe FrameMaker when it opens a specially malformed PDF. A successful attack could expose sensitive memory from the victim's system. It requires a user to open a malicious PDF, so urgency is lower than a wormable server flaw, but document-heavy teams should treat it as actionable.
Executive priority
Prioritize remediation for documentation, publishing, and engineering teams using FrameMaker. This is not a top-tier emergency from the provided evidence, but it creates avoidable confidentiality risk through malicious documents.
Technical view
CVE-2021-39835 is a CWE-416 use-after-free in Adobe FrameMaker PDF parsing. A malformed PDF can trigger sensitive memory disclosure. The CVSS 3.0 score is 4.3: network vector, low complexity, no privileges, user interaction required, confidentiality impact only.
Likely exposure
Exposure is likely limited to organizations running Adobe FrameMaker 2019 Update 8 or earlier, or FrameMaker 2020 Release Update 2 or earlier, where users may open PDFs in FrameMaker.
Exploitation context
The provided sources do not show active exploitation, and the CVE is not listed as KEV. Exploitation requires social engineering or document delivery that convinces a user to open a malicious PDF file.
Researcher notes
The bundle does not provide exploit details, proof of concept status, or explicit fixed versions. Analysis should stay scoped to FrameMaker PDF parsing, sensitive memory disclosure, and user-assisted malicious PDF opening.
Mitigation direction
- Inventory Adobe FrameMaker installations and versions.
- Review Adobe APSB21-74 for vendor remediation guidance.
- Restrict opening untrusted PDFs in FrameMaker until remediated.
- Use mail and web filtering for suspicious PDF attachments.
- Brief documentation users on unexpected PDF handling.
Validation and detection
- Confirm whether FrameMaker exists on managed endpoints.
- Identify installs at 2019 Update 8 or earlier.
- Identify installs at 2020 Release Update 2 or earlier.
- Verify remediation status against Adobe APSB21-74.
- Review alerts for suspicious PDF delivery to FrameMaker users.
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-416: 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 lookupCVE-2021-39835 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
- Medium
- CVSS
- 4.3 (3.0)
- Known Exploited
- No
- Published
Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
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:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N2.81.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.0 score
4.3MediumVector: CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://helpx.adobe.com/security/products/framemaker/apsb21-74.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.
Use After Free
Use After Free represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.