Answer in brief
CVE-2026-15308 records a Critical severity (CVSS 10.0) vulnerability in Incremental HTMLParser feed() allows CPU-exhaustion DoS via repeated unterminated markup declarations. The current sources do not mark it as known exploited. The current feed maps Python Software Foundation/CPython (generic), 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-2026-15308 records a Critical severity (CVSS 10.0) vulnerability in Incremental HTMLParser feed() allows CPU-exhaustion DoS via repeated unterminated markup declarations. The current sources do not mark it as known exploited. The current feed maps Python Software Foundation/CPython (generic), 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 10.0. 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), Python Software Foundation/CPython (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:a:python:python:*:*:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Python Software Foundation/CPythongeneric | >=0 <3.15.0b4 | 3.15.0b4 |
| Python Software Foundation/CPythongeneric | >=0 <3.14.7 || >=3.15.0a1 <3.15.0b4 | 3.14.7, 3.15.0b4 |
Published upstream
Jul 9, 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 9, 2026
The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
Quoted source text, attributed separately from HOL analysis.
CVSS is 10.0. 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), Python Software Foundation/CPython (generic). Check affected ranges and fixed versions before updating.
| Product | Affected versions | Fixed versions |
|---|---|---|
| cpe:2.3:a:python:python:*:*:*:*:*:*:*:* | Not reported | Not reported |
| Package | Affected range | Fixed version |
|---|---|---|
| Python Software Foundation/CPythongeneric | >=0 <3.15.0b4 | 3.15.0b4 |
| Python Software Foundation/CPythongeneric | >=0 <3.14.7 || >=3.15.0a1 <3.15.0b4 | 3.14.7, 3.15.0b4 |
Published upstream
Jul 9, 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 9, 2026
The incremental HTML parser (html.parser.HTMLParser) allows for CPU denial-of-service through repeated unterminated markup declarations when processing uncontrolled data.
Quoted source text, attributed separately from HOL analysis.