CVE-2023-52767 (GCVE-0-2023-52767)

Vulnerability from cvelistv5 – Published: 2024-05-21 15:30 – Updated: 2026-05-11 19:32
VLAI
Title
tls: fix NULL deref on tls_sw_splice_eof() with empty record
Summary
In the Linux kernel, the following vulnerability has been resolved: tls: fix NULL deref on tls_sw_splice_eof() with empty record syzkaller discovered that if tls_sw_splice_eof() is executed as part of sendfile() when the plaintext/ciphertext sk_msg are empty, the send path gets confused because the empty ciphertext buffer does not have enough space for the encryption overhead. This causes tls_push_record() to go on the `split = true` path (which is only supposed to be used when interacting with an attached BPF program), and then get further confused and hit the tls_merge_open_record() path, which then assumes that there must be at least one populated buffer element, leading to a NULL deref. It is possible to have empty plaintext/ciphertext buffers if we previously bailed from tls_sw_sendmsg_locked() via the tls_trim_both_msgs() path. tls_sw_push_pending_record() already handles this case correctly; let's do the same check in tls_sw_splice_eof().
Severity
No CVSS data available.
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-05-21 18:35 UTC
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 5ad627faed136089e27bcd15e0c33760e575c8c3 , < 944900fe2736c07288efe2d9394db4d3ca23f2c9 (git)
Affected: df720d288dbb1793e82b6ccbfc670ec871e9def4 , < 2214e2bb5489145aba944874d0ee1652a0a63dc8 (git)
Affected: df720d288dbb1793e82b6ccbfc670ec871e9def4 , < 53f2cb491b500897a619ff6abd72f565933760f0 (git)
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Linux Linux Affected: 6.5
Unaffected: 0 , < 6.5 (semver)
Unaffected: 6.6.4 , ≤ 6.6.* (semver)
Unaffected: 6.7 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
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            "dateUpdated": "2024-12-19T08:25:24.139Z",
            "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "shortName": "Linux"
          },
          "references": [
            {
              "url": "https://git.kernel.org/stable/c/944900fe2736c07288efe2d9394db4d3ca23f2c9"
            },
            {
              "url": "https://git.kernel.org/stable/c/2214e2bb5489145aba944874d0ee1652a0a63dc8"
            },
            {
              "url": "https://git.kernel.org/stable/c/53f2cb491b500897a619ff6abd72f565933760f0"
            }
          ],
          "title": "tls: fix NULL deref on tls_sw_splice_eof() with empty record",
          "x_generator": {
            "engine": "bippy-5f407fcff5a0"
          }
        }
      },
      "cveMetadata": {
        "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "assignerShortName": "Linux",
        "cveId": "CVE-2023-52767",
        "datePublished": "2024-05-21T15:30:50.993Z",
        "dateReserved": "2024-05-21T15:19:24.238Z",
        "dateUpdated": "2024-12-19T08:25:24.139Z",
        "state": "PUBLISHED"
      },
      "dataType": "CVE_RECORD",
      "dataVersion": "5.1"
    }
  }
}



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Tags
Taxonomy of the tags.





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

Author Source Type Date Other

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.


Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.