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CVE-2026-89044 (GCVE-0-2026-89044)

Vulnerability from cvelistv5 – Published: 2026-09-10 17:39 – Updated: 2026-09-10 17:39
VLAI
Title
Netty 4.1.133.Final through 4.1.137.Final and 4.2.13.Final through 4.2.17.Final HTTP Request Smuggling via Transfer-Encoding
Summary
Netty versions 4.1.133.Final through 4.1.137.Final and 4.2.13.Final through 4.2.17.Final fail to properly validate the final transfer coding in the Transfer-Encoding header, allowing attackers to smuggle requests by using malformed encoding declarations. Attackers can split Transfer-Encoding headers across multiple lines or use values like 'chunked, xchunked' to bypass validation and decode messages as chunked when the final coding is not chunked, enabling request smuggling attacks.
Severity
6.9 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N
CWE
  • CWE-444 - Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
Assigner
References
Impacted products
Vendor Product Version CPE status
netty netty Affected: 4.1.133.Final , < 4.1.138.Final (custom)
Affected: 4.2.13.Final , < 4.2.18.Final (custom)
guessed Create a notification for this product.
Date Public
2026-07-20 00:00
Credits
Yu Bao, PayPal Cyber Security Team dreamlike-ocean Michael-JRead
Show details on NVD website
To clipboard 

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    "dateReserved": "2026-09-10T16:45:13.890Z",
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  }
}



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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.