CVE-2026-43321 (GCVE-0-2026-43321)

Vulnerability from cvelistv5 – Published: 2026-05-08 13:26 – Updated: 2026-08-05 12:27
VLAI
Title
bpf: Properly mark live registers for indirect jumps
Summary
In the Linux kernel, the following vulnerability has been resolved: bpf: Properly mark live registers for indirect jumps For a `gotox rX` instruction the rX register should be marked as used in the compute_insn_live_regs() function. Fix this.
Severity
7.8 (High)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 493d9e0d608339a32f568504d5fd411a261bb0af , < 7beae54111c34ca63357ef120e115889b915beb5 (git)
Affected: 493d9e0d608339a32f568504d5fd411a261bb0af , < d1aab1ca576c90192ba961094d51b0be6355a4d6 (git)
guessed Create a notification for this product.
Linux Linux Affected: 6.19
Unaffected: 0 , < 6.19 (semver)
Unaffected: 6.19.6 , ≤ 6.19.* (semver)
Unaffected: 7.0 , ≤ * (original_commit_for_fix)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "kernel/bpf/verifier.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "7beae54111c34ca63357ef120e115889b915beb5",
              "status": "affected",
              "version": "493d9e0d608339a32f568504d5fd411a261bb0af",
              "versionType": "git"
            },
            {
              "lessThan": "d1aab1ca576c90192ba961094d51b0be6355a4d6",
              "status": "affected",
              "version": "493d9e0d608339a32f568504d5fd411a261bb0af",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "kernel/bpf/verifier.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "status": "affected",
              "version": "6.19"
            },
            {
              "lessThan": "6.19",
              "status": "unaffected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "6.19.*",
              "status": "unaffected",
              "version": "6.19.6",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "7.0",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "6.19.6",
                  "versionStartIncluding": "6.19",
                  "vulnerable": true
                },
                {
                  "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                  "versionEndExcluding": "7.0",
                  "versionStartIncluding": "6.19",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Properly mark live registers for indirect jumps\n\nFor a `gotox rX` instruction the rX register should be marked as used\nin the compute_insn_live_regs() function. Fix this."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "baseScore": 7.8,
            "baseSeverity": "HIGH",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
            "version": "3.1"
          },
          "scenarios": [
            {
              "lang": "en",
              "value": "AV:L - The vulnerable verifier path is reached by a local caller through the bpf() syscall with BPF_PROG_LOAD and BPF_MAP_TYPE_INSN_ARRAY setup. It is not reachable directly from network packets or a remote protocol.\nAC:L - An attacker who can load the relevant BPF program can craft bytecode and jump-table contents to reach the faulty liveness/pruning behavior without a race or victim-dependent state. The bug is deterministic verifier logic.\nPR:L - Loading the needed BPF objects is privilege-gated, but CAP_BPF/BPF-token delegated environments and namespace-based BPF delegation make this reachable by a low-privileged local attacker in reasonable deployments. Under the required tie-break rule, this is scored as low rather than high privileges.\nUI:N - No victim action is required after the attacker invokes the local BPF syscalls. The attacker supplies the program and map contents directly.\nS:U - Successful exploitation compromises the kernel in the same security authority as the vulnerable verifier. This is standard local kernel privilege escalation, not a VM or IOMMU boundary escape.\nC:H - The missing live-register mark can make verifier state pruning ignore the indirect-jump target register, potentially admitting unsafe BPF execution paths. Verifier unsoundness of this kind can be leveraged for arbitrary kernel memory disclosure.\nI:H - If an unsafe BPF program is accepted, the attacker can plausibly obtain arbitrary kernel memory write or control-flow primitives. This supports full kernel integrity compromise.\nA:H - Even without full exploitation, an accepted unsafe BPF program can corrupt kernel memory or execute invalid accesses and crash or panic the kernel. Availability impact is therefore high."
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-05T12:27:12.004Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/7beae54111c34ca63357ef120e115889b915beb5"
        },
        {
          "url": "https://git.kernel.org/stable/c/d1aab1ca576c90192ba961094d51b0be6355a4d6"
        }
      ],
      "title": "bpf: Properly mark live registers for indirect jumps",
      "x_generator": {
        "engine": "bippy-1.2.0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2026-43321",
    "datePublished": "2026-05-08T13:26:15.600Z",
    "dateReserved": "2026-05-01T14:12:56.001Z",
    "dateUpdated": "2026-08-05T12:27:12.004Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-43321",
      "date": "2026-09-28",
      "epss": "0.00165",
      "percentile": "0.05069"
    },
    "nvd": {
      "cve": {
        "affected": [
          {
            "affectedData": [
              {
                "defaultStatus": "unaffected",
                "product": "Linux",
                "programFiles": [
                  "kernel/bpf/verifier.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "lessThan": "7beae54111c34ca63357ef120e115889b915beb5",
                    "status": "affected",
                    "version": "493d9e0d608339a32f568504d5fd411a261bb0af",
                    "versionType": "git"
                  },
                  {
                    "lessThan": "d1aab1ca576c90192ba961094d51b0be6355a4d6",
                    "status": "affected",
                    "version": "493d9e0d608339a32f568504d5fd411a261bb0af",
                    "versionType": "git"
                  }
                ]
              },
              {
                "defaultStatus": "affected",
                "product": "Linux",
                "programFiles": [
                  "kernel/bpf/verifier.c"
                ],
                "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
                "vendor": "Linux",
                "versions": [
                  {
                    "status": "affected",
                    "version": "6.19"
                  },
                  {
                    "lessThan": "6.19",
                    "status": "unaffected",
                    "version": "0",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "6.19.*",
                    "status": "unaffected",
                    "version": "6.19.6",
                    "versionType": "semver"
                  },
                  {
                    "lessThanOrEqual": "*",
                    "status": "unaffected",
                    "version": "7.0",
                    "versionType": "original_commit_for_fix"
                  }
                ]
              }
            ],
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
          }
        ],
        "configurations": [
          {
            "nodes": [
              {
                "cpeMatch": [
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
                    "matchCriteriaId": "373EEEDA-FAA1-4FB4-B6ED-DB4DD99DBE67",
                    "versionEndExcluding": "6.19.6",
                    "versionStartIncluding": "6.19",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "F253B622-8837-4245-BCE5-A7BF8FC76A16",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc2:*:*:*:*:*:*",
                    "matchCriteriaId": "4AE85AD8-4641-4E7C-A2F4-305E2CD9EE64",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc3:*:*:*:*:*:*",
                    "matchCriteriaId": "F666C8D8-6538-46D4-B318-87610DE64C34",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc4:*:*:*:*:*:*",
                    "matchCriteriaId": "02259FDA-961B-47BC-AE7F-93D7EC6E90C2",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc5:*:*:*:*:*:*",
                    "matchCriteriaId": "58A9FEFF-C040-420D-8F0A-BFDAAA1DF258",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc6:*:*:*:*:*:*",
                    "matchCriteriaId": "1D2315C0-D46F-4F85-9754-F9E5E11374A6",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:7.0:rc7:*:*:*:*:*:*",
                    "matchCriteriaId": "512EE3A8-A590-4501-9A94-5D4B268D6138",
                    "vulnerable": true
                  }
                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: Properly mark live registers for indirect jumps\n\nFor a `gotox rX` instruction the rX register should be marked as used\nin the compute_insn_live_regs() function. Fix this."
          }
        ],
        "id": "CVE-2026-43321",
        "lastModified": "2026-06-17T10:49:22.673",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 7.8,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "HIGH",
                "integrityImpact": "HIGH",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 5.9,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            }
          ]
        },
        "published": "2026-05-08T14:16:40.700",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/7beae54111c34ca63357ef120e115889b915beb5"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/d1aab1ca576c90192ba961094d51b0be6355a4d6"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Analyzed",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "NVD-CWE-noinfo"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-02T12:51:03+00:00",
      "cve": "CVE-2026-43321",
      "id": "CVE-2026-43321",
      "initial_release_date": "2026-05-08T00:00:00+00:00",
      "product_status:known_affected": "260",
      "product_status:known_not_affected": "14",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: bpf: Properly mark live registers for indirect jumps",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-43321.json",
      "version": "3"
    }
  }
}



Log in or create an account to share your comment.




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.



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.