CVE-2021-21708 (GCVE-0-2021-21708)

Vulnerability from cvelistv5 – Published: 2022-02-27 08:00 – Updated: 2024-09-17 03:18
VLAI
Title
UAF due to php_filter_float() failing
Summary
In PHP versions 7.4.x below 7.4.28, 8.0.x below 8.0.16, and 8.1.x below 8.1.3, when using filter functions with FILTER_VALIDATE_FLOAT filter and min/max limits, if the filter fails, there is a possibility to trigger use of allocated memory after free, which can result it crashes, and potentially in overwrite of other memory chunks and RCE. This issue affects: code that uses FILTER_VALIDATE_FLOAT with min/max limits.
Severity
8.2 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:L
CWE
Assigner
php
References
Impacted products
Vendor Product Version
PHP Group PHP Affected: 7.4.x , < 7.4.28 (custom)
Affected: 8.0.X , < 8.0.16 (custom)
Affected: 8.1.X , < 8.1.3 (custom)
Create a notification for this product.
Date Public
2022-02-14 00:00
Credits
dukk at softdev dot online
Show details on NVD website
To clipboard 

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      "cve": "CVE-2021-21708",
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      "product_status:fixed": "1571",
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      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "php: Use after free due to php_filter_float() failing for ints",
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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.