CVE-2026-31633 (GCVE-0-2026-31633)

Vulnerability from cvelistv5 – Published: 2026-04-24 14:44 – Updated: 2026-08-05 12:23
VLAI
Title
rxrpc: Fix integer overflow in rxgk_verify_response()
Summary
In the Linux kernel, the following vulnerability has been resolved: rxrpc: Fix integer overflow in rxgk_verify_response() In rxgk_verify_response(), there's a potential integer overflow due to rounding up token_len before checking it, thereby allowing the length check to be bypassed. Fix this by checking the unrounded value against len too (len is limited as the response must fit in a single UDP packet).
Severity
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version
Linux Linux Affected: 9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a , < 1f864d9daaf622aeaa774404fd51e7d6a435b046 (git)
Affected: 9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a , < c1e242beb6b1efc3c286f617e8d940c8fbf2ed41 (git)
Affected: 9d1d2b59341f58126a69b51f9f5f8ccb9f12e54a , < 699e52180f4231c257821c037ed5c99d5eb0edb8 (git)
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Linux Linux Affected: 6.16
Unaffected: 0 , < 6.16 (semver)
Unaffected: 6.18.23 , ≤ 6.18.* (semver)
Unaffected: 6.19.13 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
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    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-02T17:14:47+00:00",
      "cve": "CVE-2026-31633",
      "id": "CVE-2026-31633",
      "initial_release_date": "2026-04-24T00:00:00+00:00",
      "product_status:known_affected": "260",
      "product_status:known_not_affected": "14",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: rxrpc: Fix integer overflow in rxgk_verify_response()",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-31633.json",
      "version": "3"
    }
  }
}



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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.