Security readout for executives and security teams
Plain-English summary
Opening a malicious Manuskript project can execute code on the user’s computer. This is not described as a server-side internet attack; it depends on convincing someone to open an untrusted project file. The vendor’s stated position is that Manuskript is not intended to open untrusted project files.
Executive priority
Treat this as a targeted-file risk, not broad perimeter exposure. Prioritize if Manuskript is used in workflows involving external collaborators or downloaded projects. If usage is rare, inventory and restrict quickly; if usage is business-critical, formalize trusted-file handling and monitor endpoints.
Technical view
CVE-2021-35196 is insecure deserialization in Manuskript through 0.12.0. The issue involves settings.py using Python pickle.load() on settings.pickle inside a project file. A crafted project file can trigger arbitrary code execution when opened. The CVSS vector requires user interaction and reports high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most likely on endpoints where Manuskript through 0.12.0 is installed and users receive or download project files from others. Shared writing workflows, email attachments, file shares, and public project downloads are the relevant paths. The provided sources do not identify exposed servers or managed cloud services.
Exploitation context
The source bundle does not show CISA KEV listing or other evidence of active exploitation. Exploitation requires a crafted project file and user interaction. The vendor disputes the threat model by saying the product is not intended for opening untrusted project files.
Researcher notes
The core weakness is CWE-502 unsafe deserialization via pickle.load(). The CVSS vector is AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H, so validation should focus on installed clients and user file-handling paths. The bundle does not name a patch level or concrete vendor mitigation.
Mitigation direction
- Do not open Manuskript project files from untrusted or unknown sources.
- Check vendor guidance and release notes for any fixed version or recommended handling change.
- Remove or restrict Manuskript where business use is unnecessary.
- Use endpoint controls to isolate document-opening workflows from sensitive systems.
- Train users to treat unexpected project files as executable-risk content.
Validation and detection
- Inventory endpoints for Manuskript installations and identify versions through 0.12.0.
- Review whether users exchange Manuskript project files externally.
- Check security telemetry for suspicious process launches after opening Manuskript projects.
- Confirm file-association and download controls reduce accidental opening of untrusted projects.
- Document any accepted risk if continued use depends on trusted-only project 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-502: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. 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-2021-35196 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://github.com/olivierkes/manuskript/issues/891CVE reference · x_refsource_MISC
- https://www.pizzapower.me/2021/06/20/arbitrary-code-execution-in-manuskript-0-12/CVE 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.
Deserialization of Untrusted Data
Deserialization of Untrusted Data represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.