MediumFix available

linux — security advisory

Type: advisorySources: OSVAdvisory ID: DEBIAN-CVE-2023-52767

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().

Products: linux
Affected versions: 6.1.27-1, 6.1.37-1, 6.1.38-1, 6.1.38-2, 6.1.38-2~bpo11+1, 6.1.38-3, 6.1.38-4, 6.1.38-4~bpo11+1, 6.1.52-1, 6.1.55-1, 6.1.55-1~bpo11+1, 6.1.64-1, 6.1.66-1, 6.1.67-1, 6.1.69-1, 6.1.69-1~bpo11+1, 6.1.76-1, 6.1.76-1~bpo11+1
Fixed versions: 6.1.82-1, 6.6.8-1
CVEs: CVE-2023-52767
Confirmed fixed CVEs: Not specified
Updated in this feed: 1 Nov 2026, 16:12 UTC · Revision 1

Source evidence

DEBIAN-CVE-2023-52767

core-osv · Original source

Published 21 May 2024, 16:15 UTC

osv:DEBIAN-CVE-2023-52767

linux

Fixed versions: 6.1.82-1

linux

Fixed versions: 6.6.8-1

linux

Fixed versions: 6.6.8-1

Complete source record

{
  "id": "e0d86b2834061d4790cbd6e39357ea6b9e82d527208410bf7fa5ff6bf30eefbc",
  "url": "https://osv.dev/vulnerability/DEBIAN-CVE-2023-52767",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "DEBIAN-CVE-2023-52767",
    "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().",
    "evidence": "osv:DEBIAN-CVE-2023-52767",
    "products": [
      {
        "name": {
          "value": "linux",
          "evidence": "/affected/0/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.1.82-1",
            "evidence": "/affected/0/ranges"
          }
        ],
        "affected_versions": [
          {
            "value": "6.1.27-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.37-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.38-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.38-2",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.38-2~bpo11+1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.38-3",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.38-4",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.38-4~bpo11+1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.52-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.55-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.55-1~bpo11+1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.64-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.66-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.67-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.69-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.69-1~bpo11+1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.76-1",
            "evidence": "/affected/0/versions"
          },
          {
            "value": "6.1.76-1~bpo11+1",
            "evidence": "/affected/0/versions"
          }
        ]
      },
      {
        "name": {
          "value": "linux",
          "evidence": "/affected/1/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.6.8-1",
            "evidence": "/affected/1/ranges"
          }
        ],
        "affected_versions": []
      },
      {
        "name": {
          "value": "linux",
          "evidence": "/affected/2/package/name"
        },
        "prerequisites": [],
        "fixed_versions": [
          {
            "value": "6.6.8-1",
            "evidence": "/affected/2/ranges"
          }
        ],
        "affected_versions": []
      }
    ],
    "severity": "medium",
    "structured": {
      "id": "DEBIAN-CVE-2023-52767",
      "aliases": [
        "DEBIAN-CVE-2023-52767"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "6.1.82-1"
                }
              ]
            }
          ],
          "package": {
            "name": "linux",
            "purl": "pkg:deb/debian/linux?arch=source&distro=bookworm",
            "ecosystem": "Debian:12"
          },
          "versions": [
            "6.1.27-1",
            "6.1.37-1",
            "6.1.38-1",
            "6.1.38-2",
            "6.1.38-2~bpo11+1",
            "6.1.38-3",
            "6.1.38-4",
            "6.1.38-4~bpo11+1",
            "6.1.52-1",
            "6.1.55-1",
            "6.1.55-1~bpo11+1",
            "6.1.64-1",
            "6.1.66-1",
            "6.1.67-1",
            "6.1.69-1",
            "6.1.69-1~bpo11+1",
            "6.1.76-1",
            "6.1.76-1~bpo11+1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-52767.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "6.6.8-1"
                }
              ]
            }
          ],
          "package": {
            "name": "linux",
            "purl": "pkg:deb/debian/linux?arch=source&distro=trixie",
            "ecosystem": "Debian:13"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-52767.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        },
        {
          "ranges": [
            {
              "type": "ECOSYSTEM",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "6.6.8-1"
                }
              ]
            }
          ],
          "package": {
            "name": "linux",
            "purl": "pkg:deb/debian/linux?arch=source&distro=forky",
            "ecosystem": "Debian:14"
          },
          "database_specific": {
            "source": "https://storage.googleapis.com/debian-osv/debian-cve-osv/DEBIAN-CVE-2023-52767.json"
          },
          "ecosystem_specific": {
            "urgency": "not yet assigned"
          }
        }
      ],
      "modified": "2026-10-26T18:02:50.927520350Z",
      "provider": "osv",
      "upstream": [
        "CVE-2023-52767"
      ],
      "references": [
        "https://security-tracker.debian.org/tracker/CVE-2023-52767"
      ]
    },
    "related_cves": [
      {
        "value": "CVE-2023-52767",
        "evidence": "/upstream"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 456991,
  "published_at": "2024-05-21T16:15:15.917+00:00"
}