CVE-2026-42582 (GCVE-0-2026-42582)

Vulnerability from cvelistv5 – Published: 2026-05-13 18:06 – Updated: 2026-05-13 19:35
VLAI
Title
Netty: HTTP/3 QPACK literal unbounded allocation
Summary
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final, when decoding header blocks, the non-Huffman branch of io.netty.handler.codec.http3.QpackDecoder#decodeHuffmanEncodedLiteral may execute new byte[length] for a string literal before verifying that length bytes are actually present in the compressed field section. The wire encoding allows a very large length to be expressed in few bytes. There is no check that length <= in.readableBytes() before new byte[length]. This vulnerability is fixed in 4.2.13.Final.
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 2026-05-13 19:35 UTC
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
  • CWE-789 - Memory Allocation with Excessive Size Value
Assigner
References
Impacted products
Vendor Product Version
netty netty Affected: >= 4.2.0.Alpha1, < 4.2.13.Final
Create a notification for this product.
io.netty netty-codec-http3 Affected: >= 4.2.0.Alpha1, < 4.2.13.Final
Create a notification for this product.
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.

Sightings

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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 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.



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