CVE-2025-68121 (GCVE-0-2025-68121)

Vulnerability from cvelistv5 – Published: 2026-02-05 17:48 – Updated: 2026-04-29 13:29
VLAI
Title
Unexpected session resumption in crypto/tls
Summary
During session resumption in crypto/tls, if the underlying Config has its ClientCAs or RootCAs fields mutated between the initial handshake and the resumed handshake, the resumed handshake may succeed when it should have failed. This may happen when a user calls Config.Clone and mutates the returned Config, or uses Config.GetConfigForClient. This can cause a client to resume a session with a server that it would not have resumed with during the initial handshake, or cause a server to resume a session with a client that it would not have resumed with during the initial handshake.
Severity
9.1 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
SSVC
Exploitation: none Automatable: yes Technical Impact: total
CISA Coordinator (v2.0.3)
CWE
  • CWE-295 - Improper Certificate Validation
Assigner
Go
References
Impacted products
Vendor Product Version
Go standard library crypto/tls Affected: 0 , < 1.24.13 (semver)
Affected: 1.25.0-0 , < 1.25.7 (semver)
Affected: 1.26.0-rc.1 , < 1.26.0-rc.3 (semver)
Create a notification for this product.
Credits
Coia Prant (github.com/rbqvq) Go Security Team
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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  • 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.


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