Answer in brief
CVE-2026-16477 records a High severity (CVSS 8.4) vulnerability in Insecure Deserialization of .cleanshot Files in CleanShot X. The current sources do not mark it as known exploited. The current feed maps MTW/CleanShot X (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.4. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps MTW/CleanShot X (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| MTW/CleanShot Xgeneric | >=4.0.0 <4.5.2 || >=4.6.0 <4.6.3 || >=4.7.0 <4.7.8 || >=4.8.0 <4.8.10 | 4.5.2, 4.6.3, 4.7.8, 4.8.10 |
Published upstream
Oct 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Oct 22, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Oct 22, 2026
CleanShot X for macOS insecurely deserializes untrusted data embedded in a .cleanshot project file (editable screenshot annotations). Exploitation requires an attacker to craft a malicious .cleanshot file, deliver it to the target, and have the target open it; the payload then executes automatically during parsing, resulting in arbitrary code execution in the context of the current user. Users who have never opened a .cleanshot file from an untrusted source are not affected by this vulnerability. This vulnerability was fixed in versions: 4.5.2, 4.6.3, 4.7.8 and 4.8.10
Quoted source text, attributed separately from HOL analysis.