CVE-2026-74435 (GCVE-0-2026-74435)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:59 – Updated: 2026-08-17 05:47
VLAI
Title
rxrpc: rxrpc_verify_data ensure rx_dec_buffer alloc
Summary
In the Linux kernel, the following vulnerability has been resolved: rxrpc: rxrpc_verify_data ensure rx_dec_buffer alloc rxrpc_recvmsg_data() calls rxrpc_verify_data() whenever the rxrpc_call.rx_dec_buffer is unallocated and assumes that upon successful return that rx_dec_buffer must be allocated. However, rxrpc_verify_data() does not request an allocation if the rxrpc_skb_priv.len is zero. In addition, failure to allocate rx_dec_buffer will result in a call to skb_copy_bits() with a NULL destination which can trigger a NULL pointer dereference. To prevent these issues rxrpc_verify_data() is modified to always attempt to allocate the rxrpc_call.rx_dec_buffer if it is NULL. This issue was identified with assistance of a private sashiko instance.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: a05bf6d9e621fa71e89ccebe3047ba45218d7b38 , < 8bbede0afced346b24e4fbde0c68cf12980ba948 (git)
Affected: b94a6ccbaf1104dd980150a65fdeb2f69d17d2f5 , < 6563b4eb38c35d75892445bcf8aacdc29914821c (git)
Affected: 46cb765e2e5ad52303ea157e10d370bb6b7acbbf , < d3b642cf95d48234590cc91450d8705a9bf6b540 (git)
Affected: d2bc90cf6c75cb96d2ce549be6c35efa3099d25b , < a962bc8508592c4d51092edac68579bd8b18fe44 (git)
Affected: d2bc90cf6c75cb96d2ce549be6c35efa3099d25b , < 16c8ae9735c5bd7e54dd7478d6348e0fc860842d (git)
Affected: c580087743712112778a06d65a4074053072d7bf (git)
Affected: 6.6.143 , < 6.6.145 (semver)
Affected: 6.12.93 , < 6.12.97 (semver)
Affected: 6.18.35 , < 6.18.40 (semver)
Affected: 7.0.11 , < 7.1 (semver)
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Linux Linux Affected: 7.1
Unaffected: 0 , < 7.1 (semver)
Unaffected: 6.6.145 , ≤ 6.6.* (semver)
Unaffected: 6.12.97 , ≤ 6.12.* (semver)
Unaffected: 6.18.40 , ≤ 6.18.* (semver)
Unaffected: 7.1.5 , ≤ 7.1.* (semver)
Unaffected: 7.2 , ≤ * (original_commit_for_fix)
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    "datePublished": "2026-08-15T05:59:34.073Z",
    "dateReserved": "2026-08-15T05:44:03.896Z",
    "dateUpdated": "2026-08-17T05:47:09.898Z",
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            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nrxrpc: rxrpc_verify_data ensure rx_dec_buffer alloc\n\nrxrpc_recvmsg_data() calls rxrpc_verify_data() whenever the\nrxrpc_call.rx_dec_buffer is unallocated and assumes that upon\nsuccessful return that rx_dec_buffer must be allocated.\nHowever, rxrpc_verify_data() does not request an allocation if\nthe rxrpc_skb_priv.len is zero.\n\nIn addition, failure to allocate rx_dec_buffer will result in a\ncall to skb_copy_bits() with a NULL destination which can\ntrigger a NULL pointer dereference.\n\nTo prevent these issues rxrpc_verify_data() is modified to\nalways attempt to allocate the rxrpc_call.rx_dec_buffer if it\nis NULL.\n\nThis issue was identified with assistance of a private\nsashiko instance."
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        "lastModified": "2026-08-17T06:19:39.153",
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                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
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      "cve": "CVE-2026-74435",
      "id": "CVE-2026-74435",
      "initial_release_date": "2026-08-15T00:00:00+00:00",
      "product_status:known_affected": "76",
      "product_status:known_not_affected": "198",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: rxrpc: rxrpc_verify_data ensure rx_dec_buffer alloc",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-74435.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.

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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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  • 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.


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