# soupsieve (PyPI) vulnerabilities

4 known vulnerabilities (2 high, 2 medium), with the versions each affects and the releases that fix them.

## At a glance

- Latest release: 4.0.1 (Nov 4, 2026): no advisory affects it
- Newest unaffected release: 4.0.1 (Nov 4, 2026), the latest release
- Weekly downloads: 77.4M
- Dependents: 34.4K
- Releases: 63 since 0.4.0 (Dec 8, 2018)
- Registry: https://pypi.org/project/soupsieve/
- Releases read: Nov 8, 2026

## Version timeline

Affected versions per advisory, in version order:

- CVE-2026-85999: 0.4.0 to 2.8.4 (2.9.0 is outside it)
- CVE-2026-86000: 0.4.0 to 2.8.4 (2.9.0 is outside it)
- CVE-2026-49476: 0.4.0 to 2.8.3 (2.8.4 is outside it)
- CVE-2026-49477: 0.4.0 to 2.8.3 (2.8.4 is outside it)

## Advisories (4)

### [CVE-2026-85999](https://cve.now/CVE-2026-85999): Soup Sieve: Polynomial-time ReDoS (O(n²)) in the whitespace/comment trimming regex \`RE\_WS\_END\` (triggers on VALID selectors)

- Severity: Medium 5.3
- Published: Sep 17, 2026
- Affected: fixed in 2.9.0.
- Fixed in 2.9.0 (released Jul 19, 2026, 60 days before disclosure).
- The latest release, 4.0.1, is not affected.

### [CVE-2026-86000](https://cve.now/CVE-2026-86000): Soup Sieve: Polynomial-time ReDoS (O(n²)) in the \`IDENTIFIER\` / \`VALUE\` selector sub-patterns

- Severity: Medium 5.3
- Published: Sep 17, 2026
- Affected: fixed in 2.9.0.
- Fixed in 2.9.0 (released Jul 19, 2026, 60 days before disclosure).
- The latest release, 4.0.1, is not affected.

### [CVE-2026-49476](https://cve.now/CVE-2026-49476): Soup Sieve: Memory Exhaustion via Large Comma-Separated Selector Lists in soupsieve

- Severity: High 7.5
- Published: Jul 14, 2026
- Affected: fixed in 2.8.4.
- Fixed in 2.8.4 (released May 24, 2026, 51 days before disclosure).
- The latest release, 4.0.1, is not affected.

### [CVE-2026-49477](https://cve.now/CVE-2026-49477): Soup Sieve: Regular Expression Denial of Service (ReDoS) in soupsieve Selector Parser

- Severity: High 7.5
- Published: Jul 14, 2026
- Affected: fixed in 2.8.4.
- Fixed in 2.8.4 (released May 24, 2026, 51 days before disclosure).
- The latest release, 4.0.1, is not affected.

---

Source: cve.now
Built by [Sazabi](https://www.sazabi.com/?utm_source=cve-now&utm_medium=markdown), AI-native observability and security: automatic issue detection, plain-language log search and live dashboards.
Page: https://cve.now/packages/pypi/soupsieve
Site guide for agents: https://cve.now/llms.txt
Uses NVD data; not endorsed by NVD.