Technology · PyPI
flask (PyPI) vulnerabilities
Updated . Rebuilt every hour.
Junglewise Threat Intelligence has tracked 5 vulnerabilities in flask (PyPI): 0 in the last 7 days and 0 in the last 90 days, 0 of them critical and 0 exploited in the wild. The most recent, CVE-2025-47278, was published on 7 July 2026.
- Last 7 days
- 0
- Last 90 days
- 0
- Critical, all time
- 0
- Exploited in the wild
- 0
About flask (PyPI)
Python web framework for building web applications.
Latest flask (PyPI) vulnerabilities
- CVE-2025-47278: PYSEC-2026-1377 - Flask uses fallback key instead of current signing keymediumCVSS 4EPSS 0.2%
- CVE-2026-27205: Flask session does not add `Vary: Cookie` header when accessed in some waysmediumCVSS 4EPSS 0.4%
- CVE-2023-30861: Flask vulnerable to possible disclosure of permanent session cookie due to missing Vary: Cookie headerlowCVSS 3.1EPSS 1.3%
- CVE-2019-1010083: Pallets Project Flask is vulnerable to Denial of Service via Unexpected memory usagelowCVSS 3.1EPSS 1.9%
- CVE-2018-1000656: Flask is vulnerable to Denial of Service via incorrect encoding of JSON datalowCVSS 3.1EPSS 3.9%
Most severe flask (PyPI) vulnerabilities
Exploited in the wild first, then by severity and CVSS score.
- CVE-2026-27205: Flask session does not add `Vary: Cookie` header when accessed in some waysmediumCVSS 4EPSS 0.4%
- CVE-2025-47278: PYSEC-2026-1377 - Flask uses fallback key instead of current signing keymediumCVSS 4EPSS 0.2%
- CVE-2018-1000656: Flask is vulnerable to Denial of Service via incorrect encoding of JSON datalowCVSS 3.1EPSS 3.9%
- CVE-2019-1010083: Pallets Project Flask is vulnerable to Denial of Service via Unexpected memory usagelowCVSS 3.1EPSS 1.9%
- CVE-2023-30861: Flask vulnerable to possible disclosure of permanent session cookie due to missing Vary: Cookie headerlowCVSS 3.1EPSS 1.3%
Vulnerabilities per week
Nothing was published in the last eight weeks. The last 13 weeks, by the week each vulnerability was published.
| Week of | Bar | Vulns | Critical |
|---|---|---|---|
| 17 Aug 2026 | 0 | 0 | |
| 24 Aug 2026 | 0 | 0 | |
| 31 Aug 2026 | 0 | 0 | |
| 7 Sep 2026 | 0 | 0 | |
| 14 Sep 2026 | 0 | 0 | |
| 21 Sep 2026 | 0 | 0 | |
| 28 Sep 2026 | 0 | 0 | |
| 5 Oct 2026 | 0 | 0 | |
| 12 Oct 2026 | 0 | 0 | |
| 19 Oct 2026 | 0 | 0 | |
| 26 Oct 2026 | 0 | 0 | |
| 2 Nov 2026 | 0 | 0 | |
| 9 Nov 2026 | 0 | 0 |
Embed a badge
A live badge for a README, a status page or an internal wiki: how many flask (PyPI) vulnerabilities were published in the last 7 days and how many of them are critical, refreshed hourly.
[](https://junglewise.ai/threats/technologies/flask)<a href="https://junglewise.ai/threats/technologies/flask"><img src="https://junglewise.ai/threats/technologies/flask/badge.svg" alt="flask (PyPI) vulnerabilities" /></a>How this is built
Junglewise Threat Intelligence collects vulnerabilities from NVD, GitHub Security Advisories, OSV, the CISA Known Exploited Vulnerabilities catalog, FIRST EPSS and vendor advisories, and matches each one to the technologies and vendors it affects. Dates are the date a vulnerability was published, in UTC.
The pages are rebuilt from the database every hour. Frozen weekly and monthly reports never change once published, so they can be cited.
Use this data
The same data is at https://junglewise.ai/threats/technologies/flask.json, and this page as text at https://junglewise.ai/threats/technologies/flask.md, for scripts and language models. It is free to reuse under CC BY 4.0 with a link back to this page.
Cite as: Junglewise Threat Intelligence, "flask (PyPI) vulnerabilities", https://junglewise.ai/threats/technologies/flask, 13 November 2026.