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CVE-2021-23437 (GCVE-0-2021-23437)

Vulnerability from cvelistv5 – Published: 2021-09-03 16:10 – Updated: 2024-09-16 20:47
VLAI
Title
Regular Expression Denial of Service (ReDoS)
Summary
The package pillow 5.2.0 and before 8.3.2 are vulnerable to Regular Expression Denial of Service (ReDoS) via the getrgb function.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
  • Regular Expression Denial of Service (ReDoS)
Assigner
References
Impacted products
Vendor Product Version CPE status
n/a Pillow Affected: 0 , < unspecified (custom)
Affected: unspecified , < 8.3.2 (custom)
Date Public
2021-09-03 00:00
Credits
Liyuan Chen
Show details on NVD website
To clipboard 

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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-03T02:09:16+00:00",
      "cve": "CVE-2021-23437",
      "id": "CVE-2021-23437",
      "initial_release_date": "2021-09-03T00:00:00+00:00",
      "product_status:known_affected": "1",
      "product_status:known_not_affected": "12",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "python-pillow: possible ReDoS via the getrgb function",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-23437.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "important",
      "current_release_date": "2026-09-02T02:24:52Z",
      "cve": "CVE-2021-23437",
      "id": "CVE-2021-23437",
      "initial_release_date": "2023-02-15T03:45:34Z",
      "product_status:known_not_affected": "48",
      "product_status:recommended": "41",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2021-23437",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2021-23437.json",
      "version": "26"
    }
  }
}



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Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.