Answer in brief
CVE-2026-4786 records a High severity (CVSS 7.1) vulnerability in Incomplete mitigation of CVE-2026-4519, %action expansion for command injection to webbrowser.open(). The current sources do not mark it as known exploited. The current feed maps Python Software Foundation/CPython (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2026-4786 records a High severity (CVSS 7.1) vulnerability in Incomplete mitigation of CVE-2026-4519, %action expansion for command injection to webbrowser.open(). The current sources do not mark it as known exploited. The current feed maps Python Software Foundation/CPython (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 7.1. 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 Python Software Foundation/CPython (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Python Software Foundation/CPythongeneric | >=0 <3.13.14 || >=3.14.0a1 <3.14.5rc1 || >=3.15.0a1 <3.15.0b1 | 3.13.14, 3.14.5rc1, 3.15.0b1 |
Published upstream
Apr 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 6, 2026
Mitgation of CVE-2026-4519 was incomplete. If the URL contained "%action" the mitigation could be bypassed for certain browser types the "webbrowser.open()" API could have commands injected into the underlying shell. See CVE-2026-4519 for details.
Quoted source text, attributed separately from HOL analysis.
CVSS is 7.1. 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 Python Software Foundation/CPython (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Python Software Foundation/CPythongeneric | >=0 <3.13.14 || >=3.14.0a1 <3.14.5rc1 || >=3.15.0a1 <3.15.0b1 | 3.13.14, 3.14.5rc1, 3.15.0b1 |
Published upstream
Apr 13, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 5, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 6, 2026
Mitgation of CVE-2026-4519 was incomplete. If the URL contained "%action" the mitigation could be bypassed for certain browser types the "webbrowser.open()" API could have commands injected into the underlying shell. See CVE-2026-4519 for details.
Quoted source text, attributed separately from HOL analysis.