Pillow Denial of Service by Uncontrolled Resource Consumption
Pillow before 8.1.2 allows attackers to cause a denial of service (memory consumption) because the reported size of a contained image is not properly checked for an ICO container, and thus an attempted memory allocation can be very large.
Affected software
Click a technology to see all vulnerabilities affecting it.
| Platform | Package | Vulnerable versions | Fixed in |
|---|---|---|---|
| Python (PyPI) | pillow | < 8.1.2 | 8.1.2 |
References
- https://pillow.readthedocs.io/en/stable/releasenotes/8.1.1.html
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TQQY6472RX4J2SUJENWDZAWKTJJGP2ML/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZTSY25UJU7NJUFHH3HWT575LT4TDFWBZ/
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/S7G44Z33J4BNI2DPDROHWGVG2U7ZH5JU/
- https://github.com/advisories/GHSA-95q3-8gr9-gm8w
- https://nvd.nist.gov/vuln/detail/CVE-2021-27923
- https://github.com/python-pillow/Pillow/commit/756fff33128a0b643d10518a26ad04b726dd8973
- https://github.com/pypa/advisory-database/tree/main/vulns/pillow/PYSEC-2021-42.yaml
- https://github.com/python-pillow/Pillow
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S7G44Z33J4BNI2DPDROHWGVG2U7ZH5JU
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/TQQY6472RX4J2SUJENWDZAWKTJJGP2ML
- https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/ZTSY25UJU7NJUFHH3HWT575LT4TDFWBZ
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/S7G44Z33J4BNI2DPDROHWGVG2U7ZH5JU
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/TQQY6472RX4J2SUJENWDZAWKTJJGP2ML
- https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/ZTSY25UJU7NJUFHH3HWT575LT4TDFWBZ
- https://pillow.readthedocs.io/en/stable/releasenotes/8.1.2.html
- https://security.gentoo.org/glsa/202107-33
- CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H- Weakness (CWE)
CWE-20, CWE-400- Platform
- Python (PyPI)
- Package
pillow- Disclosed
- 03.03.2021
- Updated
- 11.10.2026 12:19
Sources and licenses
OSV / GitHub Advisory Database - PYSEC-2021-42 - PyPA Advisory Database; CC BY 4.0
OSV / GitHub Advisory Database - GHSA-95q3-8gr9-gm8w - CC BY 4.0
Vulnerability history: pillow
All published vulnerabilities of this package (Python (PyPI)), newest first. Shows whether this is a one-off slip or a package that needs watching.
- Total entries
- 81
- First → latest
- 04.2014 10.2026
- Without a fix
- 0
- Exploited in attacks
- 1
Severity breakdown
- Critical 10
- High 53
- Medium 16
- Low 1
- Unrated 1
Disclosures per year
- 2017: 1
- 2018: 0
- 2019: 1
- 2020: 10
- 2021: 20
- 2022: 8
- 2023: 3
- 2024: 2
- 2025: 1
- 2026: 23
earlier: 12
-
Pillow Denial of Service by Uncontrolled Resource Consumption this entry
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