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CVE Record

CVE-2021-25287: An issue was discovered in Pillow before 8.2.0.

An issue was discovered in Pillow before 8.2.0. There is an out-of-bounds read in J2kDecode, in j2ku_graya_la.

UnknownCVSS not scoredNot KEV-listedUpdated
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Glexia's TakeAutomated analysisunknown

Security readout for executives and security teams

Plain-English summary

Pillow versions before 8.2.0 contain an out-of-bounds read in JPEG2000 image decoding. The main business concern is systems that process untrusted images, such as uploads, document pipelines, or media conversion services. The supplied sources do not provide a CVSS score or confirm active exploitation.

Executive priority

Treat this as a dependency hygiene issue with higher priority for internet-facing upload or media-processing services. There is no supplied evidence of active exploitation, but image parsers are commonly exposed to untrusted data.

Technical view

CVE-2021-25287 is an out-of-bounds read in Pillow J2kDecode, specifically j2ku_graya_la, fixed in Pillow 8.2.0. Evidence points to JPEG2000 decoding exposure. The source bundle does not state confidentiality, integrity, availability impact, CWE, or exploitability details.

Likely exposure

Exposure is most likely where Python applications use Pillow before 8.2.0 to decode JPEG2000 content from users, partners, email, documents, or automated ingestion systems. Systems using OS packages may be covered by Fedora or Gentoo vendor updates.

Exploitation context

The bundle does not report active exploitation, and KEV is false. A practical attack would depend on getting a vulnerable application to process crafted JPEG2000 data, but the provided sources do not include exploit maturity or attack complexity details.

Researcher notes

The public record is sparse: no CVSS, CWE, or detailed impact is included in the bundle. Anchor validation on Pillow version, JPEG2000 decoding reachability, and whether the runtime uses upstream pip packages or distro-backported builds.

Mitigation direction

  • Upgrade Pillow to 8.2.0 or later where applications vendor Python dependencies.
  • Apply Fedora or Gentoo patched packages where Pillow is OS-managed.
  • Check vendor guidance for any platform-specific backports or package names.
  • Reduce processing of untrusted JPEG2000 files until vulnerable versions are remediated.

Validation and detection

  • Inventory Python environments for Pillow versions earlier than 8.2.0.
  • Check application paths that accept or transform JPEG2000 images.
  • Confirm deployed containers and virtual environments use the patched dependency.
  • Review OS package advisories for backported fixes if version strings differ.
Prepared
Confidence
medium
Sources
6

Public sources used

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.

Potential ATT&CK relevance

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Vulnerability profileCVE Program record
Severity
Unknown
CVSS
Not scored
Known Exploited
No
Published
Official CVE source material

CNA and ADP enrichment extracted from CVE v5

These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.

0CVSS vectors
0Timeline events
0ADP providers
5Source links

CVSS and timeline data

No CVSS vectors or timeline events were available in the normalized CVE source material.

Source materials

Affected products

Products and packages named in the record

VendorProductVersion / packageStatus
n/an/an/aListed
Weakness

CWE details

No CWE listed

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