Uncontrolled Resource Consumption in pillow

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

Impact _Pillow before 8.1.1 allows attackers to cause a denial of service (memory consumption) because the reported size of a contained image is not properly checked for a BLP container, and thus an attempted memory allocation can be very large._

Patches _An issue was discovered in Pillow before 6.2.0. When reading specially crafted invalid image files, the library can either allocate very large amounts of memory or take an extremely long period of time to process the image._

Workarounds _An issue was discovered in Pillow before 6.2.0. When reading specially crafted invalid image files, the library can either allocate very large amounts of memory or take an extremely long period of time to process the image._

References https://nvd.nist.gov/vuln/detail/CVE-2021-27921

For more information If you have any questions or comments about this advisory: * Open an issue in example link to repo * Email us at example email…

Published by the source

23 Apr 2021, 16:54 UTC

Last modified by the source

2 Dec 2024, 05:42 UTC

Source last checked

27 Oct 2026, 19:05 UTC

1. Revision 2 · withdrawn · 27 Oct 2026

   Withdrawn upstream: ghsa record GHSA-jgpv-4h4c-xhw3

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-jgpv-4h4c-xhw3

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# Patch Next advisory brief: GHSA-jgpv-4h4c-xhw3

Advisory: Uncontrolled Resource Consumption in pillow
IDs: GHSA-jgpv-4h4c-xhw3
Record: https://patchnext.com/advisories/ghsa-jgpv-4h4c-xhw3 (revision 2, source checked 27 Oct 2026, 19:05 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: pillow 8.1.2. A vendor fix does not mean a deployment is fixed.
Status: WITHDRAWN upstream. Do not act on this record without new evidence.

## Affected components
- PyPI pillow: affected < 8.1.2; fixed in 8.1.2

## Suggested inspection (read-only)
- `python -m pip show pillow`: prints the installed version. Run with the environment that serves production active.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on pillow.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-jgpv-4h4c-xhw3 (OSV record GHSA-jgpv-4h4c-xhw3 lists affected ranges: PyPI pillow >=0 <8.1.2 (fixed))
- Verified: https://github.com/advisories/GHSA-jgpv-4h4c-xhw3 (ghsa record GHSA-jgpv-4h4c-xhw3 is marked withdrawn upstream (as of 2026-10-27T19:00:26Z).)

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