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CVE-2025-47908 (GCVE-0-2025-47908)

Vulnerability from cvelistv5 – Published: 2025-08-06 20:41 – Updated: 2025-08-07 13:47
VLAI
Title
Denial of service via malicious preflight requests in github.com/rs/cors
Summary
Middleware causes a prohibitive amount of heap allocations when processing malicious preflight requests that include a Access-Control-Request-Headers (ACRH) header whose value contains many commas. This behavior can be abused by attackers to produce undue load on the middleware/server as an attempt to cause a denial of service.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-08-07 13:46 UTC
CWE
  • CWE-1325 - Improperly Controlled Sequential Memory Allocation
Assigner
References
Impacted products
Vendor Product Version CPE status
github.com/rs/cors github.com/rs/cors Affected: 1.9.0 , < 1.11.0 (semver)
guessed Create a notification for this product.
Credits
@jub0bs
Show details on NVD website
To clipboard 

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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.

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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.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.


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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.