Vulnerability-Lookup

FKIE_CVE-2026-72330

Vulnerability from fkie_nvd - Published: 2026-08-15 06:22 - Updated: 2026-08-17 06:18

Severity

7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Summary

In the Linux kernel, the following vulnerability has been resolved: net/tls: Consume empty data records in tls_sw_read_sock() A peer may send a zero-length TLS application_data record; TLS 1.3 explicitly permits these as a traffic-analysis countermeasure (RFC 8446, Section 5.1). After decryption such a record has full_len == 0. tls_sw_read_sock() hands it to the read_actor, which has no payload to consume and returns zero. The loop treats a zero return as backpressure (used <= 0), requeues the skb at the head of rx_list, and stops. rx_list is serviced head-first on the next call, so the empty record is dequeued, fails the same way, and is requeued again; every later record on the connection is blocked behind it. tls_sw_recvmsg() does not stall on this: a zero-length data record copies nothing and falls through to consume_skb(). Mirror that in the read_sock() path by recognizing an empty data record before the actor runs, consuming it, and continuing.

References

	URL	Tags
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/0867b0f2513ebc1c475af9898c97f4772a68d964
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/3be28e2c9cd0230cb51fd4967df095273afd3848
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/c6b440cf766a557b08d25f1b571b3d57d039686e
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/e8a4c9fc437b16aef38f86ce3275677e36924259
	416baaa9-dc9f-4396-8d5f-8c081fb06d67	https://git.kernel.org/stable/c/ebc295ce343600c2d60c1e1e0c5d192080217457

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/tls/tls_sw.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "0867b0f2513ebc1c475af9898c97f4772a68d964",
              "status": "affected",
              "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945",
              "versionType": "git"
            },
            {
              "lessThan": "c6b440cf766a557b08d25f1b571b3d57d039686e",
              "status": "affected",
              "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945",
              "versionType": "git"
            },
            {
              "lessThan": "e8a4c9fc437b16aef38f86ce3275677e36924259",
              "status": "affected",
              "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945",
              "versionType": "git"
            },
            {
              "lessThan": "ebc295ce343600c2d60c1e1e0c5d192080217457",
              "status": "affected",
              "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945",
              "versionType": "git"
            },
            {
              "lessThan": "3be28e2c9cd0230cb51fd4967df095273afd3848",
              "status": "affected",
              "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/tls/tls_sw.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.6"
            },
            {
              "lessThan": "6.6",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/tls: Consume empty data records in tls_sw_read_sock()\n\nA peer may send a zero-length TLS application_data record; TLS 1.3\nexplicitly permits these as a traffic-analysis countermeasure (RFC\n8446, Section 5.1). After decryption such a record has full_len ==\n0. tls_sw_read_sock() hands it to the read_actor, which has no\npayload to consume and returns zero. The loop treats a zero return\nas backpressure (used \u003c= 0), requeues the skb at the head of\nrx_list, and stops. rx_list is serviced head-first on the next\ncall, so the empty record is dequeued, fails the same way, and is\nrequeued again; every later record on the connection is blocked\nbehind it.\n\ntls_sw_recvmsg() does not stall on this: a zero-length data record\ncopies nothing and falls through to consume_skb(). Mirror that in\nthe read_sock() path by recognizing an empty data record before\nthe actor runs, consuming it, and continuing."
    }
  ],
  "id": "CVE-2026-72330",
  "lastModified": "2026-08-17T06:18:36.580",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "type": "Secondary"
      }
    ]
  },
  "published": "2026-08-15T06:22:06.080",
  "references": [
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/0867b0f2513ebc1c475af9898c97f4772a68d964"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/3be28e2c9cd0230cb51fd4967df095273afd3848"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/c6b440cf766a557b08d25f1b571b3d57d039686e"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/e8a4c9fc437b16aef38f86ce3275677e36924259"
    },
    {
      "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
      "url": "https://git.kernel.org/stable/c/ebc295ce343600c2d60c1e1e0c5d192080217457"
    }
  ],
  "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
  "vulnStatus": "Received"
}

CVE-2026-72330 (GCVE-0-2026-72330)

Vulnerability from cvelistv5 – Published: 2026-08-15 05:55 – Updated: 2026-08-17 05:42

Title

net/tls: Consume empty data records in tls_sw_read_sock()

Summary

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Assigner

Linux mitre root

References

5 references

URL	Tags
https://git.kernel.org/stable/c/0867b0f2513ebc1c4…
https://git.kernel.org/stable/c/c6b440cf766a557b0…
https://git.kernel.org/stable/c/e8a4c9fc437b16aef…
https://git.kernel.org/stable/c/ebc295ce343600c2d…
https://git.kernel.org/stable/c/3be28e2c9cd0230cb…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 662fbcec32f4af6bdcf5b4006b792ebe9543d945 , < 0867b0f2513ebc1c475af9898c97f4772a68d964 (git) Affected: 662fbcec32f4af6bdcf5b4006b792ebe9543d945 , < c6b440cf766a557b08d25f1b571b3d57d039686e (git) Affected: 662fbcec32f4af6bdcf5b4006b792ebe9543d945 , < e8a4c9fc437b16aef38f86ce3275677e36924259 (git) Affected: 662fbcec32f4af6bdcf5b4006b792ebe9543d945 , < ebc295ce343600c2d60c1e1e0c5d192080217457 (git) Affected: 662fbcec32f4af6bdcf5b4006b792ebe9543d945 , < 3be28e2c9cd0230cb51fd4967df095273afd3848 (git)
Linux	Linux	Affected: 6.6 Unaffected: 0 , < 6.6 (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)

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "net/tls/tls_sw.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "0867b0f2513ebc1c475af9898c97f4772a68d964",
              "status": "affected",
              "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945",
              "versionType": "git"
            },
            {
              "lessThan": "c6b440cf766a557b08d25f1b571b3d57d039686e",
              "status": "affected",
              "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945",
              "versionType": "git"
            },
            {
              "lessThan": "e8a4c9fc437b16aef38f86ce3275677e36924259",
              "status": "affected",
              "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945",
              "versionType": "git"
            },
            {
              "lessThan": "ebc295ce343600c2d60c1e1e0c5d192080217457",
              "status": "affected",
              "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945",
              "versionType": "git"
            },
            {
              "lessThan": "3be28e2c9cd0230cb51fd4967df095273afd3848",
              "status": "affected",
              "version": "662fbcec32f4af6bdcf5b4006b792ebe9543d945",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "net/tls/tls_sw.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.6"
            },
            {
              "lessThan": "6.6",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.145",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.12.*",
              "status": "unaffected",
              "version": "6.12.97",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.18.*",
              "status": "unaffected",
              "version": "6.18.40",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "7.1.*",
              "status": "unaffected",
              "version": "7.1.5",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.2",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.6.145",
                  "versionStartIncluding": "6.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.12.97",
                  "versionStartIncluding": "6.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.18.40",
                  "versionStartIncluding": "6.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.1.5",
                  "versionStartIncluding": "6.6",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.2",
                  "versionStartIncluding": "6.6",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/tls: Consume empty data records in tls_sw_read_sock()\n\nA peer may send a zero-length TLS application_data record; TLS 1.3\nexplicitly permits these as a traffic-analysis countermeasure (RFC\n8446, Section 5.1). After decryption such a record has full_len ==\n0. tls_sw_read_sock() hands it to the read_actor, which has no\npayload to consume and returns zero. The loop treats a zero return\nas backpressure (used \u003c= 0), requeues the skb at the head of\nrx_list, and stops. rx_list is serviced head-first on the next\ncall, so the empty record is dequeued, fails the same way, and is\nrequeued again; every later record on the connection is blocked\nbehind it.\n\ntls_sw_recvmsg() does not stall on this: a zero-length data record\ncopies nothing and falls through to consume_skb(). Mirror that in\nthe read_sock() path by recognizing an empty data record before\nthe actor runs, consuming it, and continuing."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.5,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:N - A remote TLS peer sends zero-length TLS 1.3 application_data records over TCP; they are decrypted in the kTLS software RX path and processed in tls_sw_read_sock(), reachable from network-facing consumers such as NVMe-over-TCP host I/O via sock-\u003eops-\u003eread_sock.\nAC:L - After a normal TLS handshake, sending a standards-compliant zero-length application_data record reliably reproduces the stall; no races, special memory layout, or rare timing are required.\nPR:N - Exploitation requires only being the remote TLS peer on an established kTLS connection (e.g. a malicious NVMe-oF target); no local account, capability, namespace, or administrator privileges on the victim host are needed.\nUI:N - No victim user action beyond the system maintaining its normal encrypted network connection; the attacker triggers the flaw by sending protocol-valid TLS records.\nS:U - Impact is confined to stalling the affected TLS/kTLS connection and its dependent service I/O; it does not cross a security boundary such as guest-to-host escape or sandbox breakout.\nC:N - The flaw is a receive-path logic error that requeues an empty skb indefinitely; there is no out-of-bounds access, use-after-free, or other memory corruption that could disclose kernel or application data.\nI:N - The bug does not modify kernel memory, credentials, or application data; it only prevents forward progress on the stalled connection by blocking consumption of subsequent decrypted records.\nA:H - The empty record is permanently requeued at the head of rx_list, creating a repeatable deadlock that blocks all later traffic on the connection and can hang NVMe-over-TCP (or similar read_sock) I/O until the connection is torn down."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-17T05:42:52.302Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/0867b0f2513ebc1c475af9898c97f4772a68d964"
        },
        {
          "url": "https://git.kernel.org/stable/c/c6b440cf766a557b08d25f1b571b3d57d039686e"
        },
        {
          "url": "https://git.kernel.org/stable/c/e8a4c9fc437b16aef38f86ce3275677e36924259"
        },
        {
          "url": "https://git.kernel.org/stable/c/ebc295ce343600c2d60c1e1e0c5d192080217457"
        },
        {
          "url": "https://git.kernel.org/stable/c/3be28e2c9cd0230cb51fd4967df095273afd3848"
        }
      ],
      "title": "net/tls: Consume empty data records in tls_sw_read_sock()",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-72330",
    "datePublished": "2026-08-15T05:55:40.555Z",
    "dateReserved": "2026-08-09T03:40:39.919Z",
    "dateUpdated": "2026-08-17T05:42:52.302Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

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.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.

Action not permitted

FKIE_CVE-2026-72330

CVE-2026-72330 (GCVE-0-2026-72330)

Tags

Sightings

Nomenclature