CVE-2026-42505 (GCVE-0-2026-42505)

Vulnerability from cvelistv5 – Published: 2026-07-08 15:46 – Updated: 2026-07-08 19:38
VLAI
Title
Invoking Encrypted Client Hello privacy leak in crypto/tls
Summary
Handshakes which used Encrypted Client Hello could be de-anonymized by a passive network observer due to a disclosure of pre-shared key identities in the unencrypted client hello.
Severity
5.3 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: partial
CISA Coordinator (v2.0.3)
CWE
  • CWE-201 - Insertion of Sensitive Information Into Sent Data
Assigner
Go
References
Impacted products
Vendor Product Version
Go standard library crypto/tls Affected: 0 , < 1.25.12 (semver)
Affected: 1.26.0-0 , < 1.26.5 (semver)
Affected: 1.27.0-0 , < 1.27.0-rc.2 (semver)
Create a notification for this product.
Credits
Coia Prant (github.com/rbqvq)
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.
  • 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.