CVE-2026-6679 (GCVE-0-2026-6679)

Vulnerability from cvelistv5 – Published: 2026-06-25 20:13 – Updated: 2026-06-26 13:13
VLAI
Title
DTLS 1.3 ACK serialization heap buffer overflow via integer truncation
Summary
A heap buffer overflow could occur in the DTLS 1.3 ACK serialization path before the connecting peer is authenticated. The buffer overflow was due to an integer truncation when computing the length of the ACK record-number list, causing an undersized buffer to be allocated and then overrun. This affects builds using DTLS 1.3 and wolfSSL version 5.9.0 and earlier. A fix was added to the 5.9.1 release.
Severity
8.8 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:H/SC:N/SI:N/SA:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-787 - Out-of-bounds Write
  • CWE-190 - Integer Overflow or Wraparound
  • CWE-197 - Numeric Truncation Error
Assigner
References
Impacted products
Vendor Product Version
wolfSSL wolfSSL Affected: 5.4.0 , ≤ 5.9.0 (semver)
Create a notification for this product.
Credits
Nicholas Carlini from Anthropic
Show details on NVD website
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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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  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


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