csaf_certbund - wid-sec-w-2024-3337

wid-sec-w-2024-3337

Vulnerability from csaf_certbund

Published

2024-11-04 23:00

Modified

2024-11-04 23:00

Summary

Linux Kernel: Schwachstelle ermöglicht Umgehen von Sicherheitsvorkehrungen

Notes

Das BSI ist als Anbieter für die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch dafür verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgfältig im Einzelfall zu prüfen.

Produktbeschreibung

Der Kernel stellt den Kern des Linux Betriebssystems dar.

Angriff

Ein lokaler Angreifer kann eine Schwachstelle im Linux Kernel ausnutzen, um Sicherheitsvorkehrungen zu umgehen.

Betroffene Betriebssysteme

- Linux

JSON

To clipboard

{
  "document": {
    "aggregate_severity": {
      "text": "mittel"
    },
    "category": "csaf_base",
    "csaf_version": "2.0",
    "distribution": {
      "tlp": {
        "label": "WHITE",
        "url": "https://www.first.org/tlp/"
      }
    },
    "lang": "de-DE",
    "notes": [
      {
        "category": "legal_disclaimer",
        "text": "Das BSI ist als Anbieter f\u00fcr die eigenen, zur Nutzung bereitgestellten Inhalte nach den allgemeinen Gesetzen verantwortlich. Nutzerinnen und Nutzer sind jedoch daf\u00fcr verantwortlich, die Verwendung und/oder die Umsetzung der mit den Inhalten bereitgestellten Informationen sorgf\u00e4ltig im Einzelfall zu pr\u00fcfen."
      },
      {
        "category": "description",
        "text": "Der Kernel stellt den Kern des Linux Betriebssystems dar.",
        "title": "Produktbeschreibung"
      },
      {
        "category": "summary",
        "text": "Ein lokaler Angreifer kann eine Schwachstelle im Linux Kernel ausnutzen, um Sicherheitsvorkehrungen zu umgehen.",
        "title": "Angriff"
      },
      {
        "category": "general",
        "text": "- Linux",
        "title": "Betroffene Betriebssysteme"
      }
    ],
    "publisher": {
      "category": "other",
      "contact_details": "csaf-provider@cert-bund.de",
      "name": "Bundesamt f\u00fcr Sicherheit in der Informationstechnik",
      "namespace": "https://www.bsi.bund.de"
    },
    "references": [
      {
        "category": "self",
        "summary": "WID-SEC-W-2024-3337 - CSAF Version",
        "url": "https://wid.cert-bund.de/.well-known/csaf/white/2024/wid-sec-w-2024-3337.json"
      },
      {
        "category": "self",
        "summary": "WID-SEC-2024-3337 - Portal Version",
        "url": "https://wid.cert-bund.de/portal/wid/securityadvisory?name=WID-SEC-2024-3337"
      },
      {
        "category": "external",
        "summary": "Linux Kernel CVE-2023-52920 vom 2024-11-04",
        "url": "http://lore.kernel.org/linux-cve-announce/2024110518-CVE-2023-52920-17f6@gregkh/"
      }
    ],
    "source_lang": "en-US",
    "title": "Linux Kernel: Schwachstelle erm\u00f6glicht Umgehen von Sicherheitsvorkehrungen",
    "tracking": {
      "current_release_date": "2024-11-04T23:00:00.000+00:00",
      "generator": {
        "date": "2024-11-05T12:40:10.101+00:00",
        "engine": {
          "name": "BSI-WID",
          "version": "1.3.8"
        }
      },
      "id": "WID-SEC-W-2024-3337",
      "initial_release_date": "2024-11-04T23:00:00.000+00:00",
      "revision_history": [
        {
          "date": "2024-11-04T23:00:00.000+00:00",
          "number": "1",
          "summary": "Initiale Fassung"
        }
      ],
      "status": "final",
      "version": "1"
    }
  },
  "product_tree": {
    "branches": [
      {
        "branches": [
          {
            "branches": [
              {
                "category": "product_version_range",
                "name": "\u003c6.8",
                "product": {
                  "name": "Open Source Linux Kernel \u003c6.8",
                  "product_id": "T033929"
                }
              },
              {
                "category": "product_version",
                "name": "6.8",
                "product": {
                  "name": "Open Source Linux Kernel 6.8",
                  "product_id": "T033929-fixed",
                  "product_identification_helper": {
                    "cpe": "cpe:/o:linux:linux_kernel:6.8"
                  }
                }
              }
            ],
            "category": "product_name",
            "name": "Linux Kernel"
          }
        ],
        "category": "vendor",
        "name": "Open Source"
      }
    ]
  },
  "vulnerabilities": [
    {
      "cve": "CVE-2023-52920",
      "notes": [
        {
          "category": "description",
          "text": "Es besteht eine Schwachstelle im Linux Kernel. Dieser Fehler existiert wegen einer unzureichenden Verfolgung von Register-Spill/Fill-Operationen zum und vom Stack in der Pr\u00e4zisionsverfolgungskomponente des BPF-Verifizierers, was eine falsche Verifizierung bestimmter Operationen erm\u00f6glicht. Ein lokaler Angreifer kann diese Schwachstelle ausnutzen, um Sicherheits\u00fcberpr\u00fcfungen zu umgehen."
        }
      ],
      "product_status": {
        "known_affected": [
          "T033929"
        ]
      },
      "release_date": "2024-11-04T23:00:00.000+00:00",
      "title": "CVE-2023-52920"
    }
  ]
}

cve-2023-52920

Vulnerability from cvelistv5

Published

2024-11-05 10:09

Modified

2024-12-19 08:28

Severity ?

Summary

In the Linux kernel, the following vulnerability has been resolved: bpf: support non-r10 register spill/fill to/from stack in precision tracking Use instruction (jump) history to record instructions that performed register spill/fill to/from stack, regardless if this was done through read-only r10 register, or any other register after copying r10 into it *and* potentially adjusting offset. To make this work reliably, we push extra per-instruction flags into instruction history, encoding stack slot index (spi) and stack frame number in extra 10 bit flags we take away from prev_idx in instruction history. We don't touch idx field for maximum performance, as it's checked most frequently during backtracking. This change removes basically the last remaining practical limitation of precision backtracking logic in BPF verifier. It fixes known deficiencies, but also opens up new opportunities to reduce number of verified states, explored in the subsequent patches. There are only three differences in selftests' BPF object files according to veristat, all in the positive direction (less states). File Program Insns (A) Insns (B) Insns (DIFF) States (A) States (B) States (DIFF) -------------------------------------- ------------- --------- --------- ------------- ---------- ---------- ------------- test_cls_redirect_dynptr.bpf.linked3.o cls_redirect 2987 2864 -123 (-4.12%) 240 231 -9 (-3.75%) xdp_synproxy_kern.bpf.linked3.o syncookie_tc 82848 82661 -187 (-0.23%) 5107 5073 -34 (-0.67%) xdp_synproxy_kern.bpf.linked3.o syncookie_xdp 85116 84964 -152 (-0.18%) 5162 5130 -32 (-0.62%) Note, I avoided renaming jmp_history to more generic insn_hist to minimize number of lines changed and potential merge conflicts between bpf and bpf-next trees. Notice also cur_hist_entry pointer reset to NULL at the beginning of instruction verification loop. This pointer avoids the problem of relying on last jump history entry's insn_idx to determine whether we already have entry for current instruction or not. It can happen that we added jump history entry because current instruction is_jmp_point(), but also we need to add instruction flags for stack access. In this case, we don't want to entries, so we need to reuse last added entry, if it is present. Relying on insn_idx comparison has the same ambiguity problem as the one that was fixed recently in [0], so we avoid that. [0] https://patchwork.kernel.org/project/netdevbpf/patch/20231110002638.4168352-3-andrii@kernel.org/

References

▼	URL	Tags
	https://git.kernel.org/stable/c/ecc2aeeaa08a355d84d3ca9c3d2512399a194f29
	https://git.kernel.org/stable/c/41f6f64e6999a837048b1bd13a2f8742964eca6b

Impacted products

Vendor

Product

Version

▼

Linux

Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2
Version: 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2

Linux

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "Linux",
          "programFiles": [
            "include/linux/bpf_verifier.h",
            "kernel/bpf/verifier.c",
            "tools/testing/selftests/bpf/progs/verifier_subprog_precision.c",
            "tools/testing/selftests/bpf/verifier/precise.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThan": "ecc2aeeaa08a355d84d3ca9c3d2512399a194f29",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            },
            {
              "lessThan": "41f6f64e6999a837048b1bd13a2f8742964eca6b",
              "status": "affected",
              "version": "1da177e4c3f41524e886b7f1b8a0c1fc7321cac2",
              "versionType": "git"
            }
          ]
        },
        {
          "defaultStatus": "affected",
          "product": "Linux",
          "programFiles": [
            "include/linux/bpf_verifier.h",
            "kernel/bpf/verifier.c",
            "tools/testing/selftests/bpf/progs/verifier_subprog_precision.c",
            "tools/testing/selftests/bpf/verifier/precise.c"
          ],
          "repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
          "vendor": "Linux",
          "versions": [
            {
              "lessThanOrEqual": "6.6.*",
              "status": "unaffected",
              "version": "6.6.64",
              "versionType": "semver"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "6.8",
              "versionType": "original_commit_for_fix"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nbpf: support non-r10 register spill/fill to/from stack in precision tracking\n\nUse instruction (jump) history to record instructions that performed\nregister spill/fill to/from stack, regardless if this was done through\nread-only r10 register, or any other register after copying r10 into it\n*and* potentially adjusting offset.\n\nTo make this work reliably, we push extra per-instruction flags into\ninstruction history, encoding stack slot index (spi) and stack frame\nnumber in extra 10 bit flags we take away from prev_idx in instruction\nhistory. We don\u0027t touch idx field for maximum performance, as it\u0027s\nchecked most frequently during backtracking.\n\nThis change removes basically the last remaining practical limitation of\nprecision backtracking logic in BPF verifier. It fixes known\ndeficiencies, but also opens up new opportunities to reduce number of\nverified states, explored in the subsequent patches.\n\nThere are only three differences in selftests\u0027 BPF object files\naccording to veristat, all in the positive direction (less states).\n\nFile                                    Program        Insns (A)  Insns (B)  Insns  (DIFF)  States (A)  States (B)  States (DIFF)\n--------------------------------------  -------------  ---------  ---------  -------------  ----------  ----------  -------------\ntest_cls_redirect_dynptr.bpf.linked3.o  cls_redirect        2987       2864  -123 (-4.12%)         240         231    -9 (-3.75%)\nxdp_synproxy_kern.bpf.linked3.o         syncookie_tc       82848      82661  -187 (-0.23%)        5107        5073   -34 (-0.67%)\nxdp_synproxy_kern.bpf.linked3.o         syncookie_xdp      85116      84964  -152 (-0.18%)        5162        5130   -32 (-0.62%)\n\nNote, I avoided renaming jmp_history to more generic insn_hist to\nminimize number of lines changed and potential merge conflicts between\nbpf and bpf-next trees.\n\nNotice also cur_hist_entry pointer reset to NULL at the beginning of\ninstruction verification loop. This pointer avoids the problem of\nrelying on last jump history entry\u0027s insn_idx to determine whether we\nalready have entry for current instruction or not. It can happen that we\nadded jump history entry because current instruction is_jmp_point(), but\nalso we need to add instruction flags for stack access. In this case, we\ndon\u0027t want to entries, so we need to reuse last added entry, if it is\npresent.\n\nRelying on insn_idx comparison has the same ambiguity problem as the one\nthat was fixed recently in [0], so we avoid that.\n\n  [0] https://patchwork.kernel.org/project/netdevbpf/patch/20231110002638.4168352-3-andrii@kernel.org/"
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2024-12-19T08:28:34.900Z",
        "orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "shortName": "Linux"
      },
      "references": [
        {
          "url": "https://git.kernel.org/stable/c/ecc2aeeaa08a355d84d3ca9c3d2512399a194f29"
        },
        {
          "url": "https://git.kernel.org/stable/c/41f6f64e6999a837048b1bd13a2f8742964eca6b"
        }
      ],
      "title": "bpf: support non-r10 register spill/fill to/from stack in precision tracking",
      "x_generator": {
        "engine": "bippy-5f407fcff5a0"
      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
    "assignerShortName": "Linux",
    "cveId": "CVE-2023-52920",
    "datePublished": "2024-11-05T10:09:30.280Z",
    "dateReserved": "2024-08-21T06:07:11.017Z",
    "dateUpdated": "2024-12-19T08:28:34.900Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

Sightings

Author	Source	Type	Date

Nomenclature

Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
Confirmed: The vulnerability is confirmed from an analyst perspective.
Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
Patched: This vulnerability was successfully patched by the user reporting the sighting.
Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
Not confirmed: The user expresses doubt about the veracity of the vulnerability.
Not patched: This vulnerability was not successfully patched by the user reporting the sighting.

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