Vulnerability-Lookup

UBUNTU-CVE-2026-71967 (CVE-2026-71967)

Vulnerability from osv_ubuntu – Published: 2026-08-10 19:17 – Updated: 2026-08-10 19:17 – Source website

Details

OP-TEE OS through 4.10.0, fixed in commit 0aadfc2, contains a null pointer dereference vulnerability in the Widevine pseudo-TA open_session handler that allows Normal World clients to cause a denial of service when CFG_WIDEVINE_PTA is enabled. Attackers can open a session directly on the Widevine PTA to trigger an unconditional dereference of a NULL calling session pointer via is_user_ta_ctx(), faulting the TEE at S-EL1 and crashing the trusted execution environment.

Severity

5.5 (Medium)


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

5.7 (Medium)


                    
                      CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-71967	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-71967	REPORT
	https://github.com/OP-TEE/optee_os/commit/0aadfc2…	REPORT
	https://github.com/OP-TEE/optee_os/pull/7899	REPORT
	https://www.vulncheck.com/advisories/op-tee-os-nu…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "optee-os",
            "binary_version": "4.8.0-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "optee-os",
        "purl": "pkg:deb/ubuntu/optee-os@4.8.0-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "4.7.0-1",
        "4.8.0-1"
      ]
    }
  ],
  "aliases": [],
  "details": "OP-TEE OS through 4.10.0, fixed in commit 0aadfc2, contains a null pointer dereference vulnerability in the Widevine pseudo-TA open_session handler that allows Normal World clients to cause a denial of service when CFG_WIDEVINE_PTA is enabled. Attackers can open a session directly on the Widevine PTA to trigger an unconditional dereference of a NULL calling session pointer via is_user_ta_ctx(), faulting the TEE at S-EL1 and crashing the trusted execution environment.",
  "id": "UBUNTU-CVE-2026-71967",
  "modified": "2026-08-10T19:17:00Z",
  "published": "2026-08-10T19:17:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-71967"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-71967"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/OP-TEE/optee_os/commit/0aadfc23407f50e770eb5ddd871fc208f5626833"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/OP-TEE/optee_os/pull/7899"
    },
    {
      "type": "REPORT",
      "url": "https://www.vulncheck.com/advisories/op-tee-os-null-pointer-dereference-dos-via-widevine-pta-open-session"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-71967"
  ]
}

CVE-2026-71967 (GCVE-0-2026-71967)

Vulnerability from cvelistv5 – Published: 2026-08-10 18:11 – Updated: 2026-08-14 16:51 X_Open Source

Title

OP-TEE OS 4.10.0 NULL Pointer Dereference DoS via Widevine PTA open_session

Summary

Severity

5.7 (Medium)


                        
                          CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

5.5 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-08-10 18:58 UTC

CWE

CWE-476 - NULL Pointer Dereference

Assigner

VulnCheck mitre root

References

3 references

URL	Tags
https://github.com/OP-TEE/optee_os/pull/7899	issue-tracking
https://github.com/OP-TEE/optee_os/commit/0aadfc2…	patch
https://www.vulncheck.com/advisories/op-tee-os-nu…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
OP-TEE	optee_os	Affected: 0 , ≤ 4.10.0 (semver) Unaffected: 0aadfc23407f50e770eb5ddd871fc208f5626833 (git) cpe:2.3:o:op-tee:op-tee_os::::::::

Date Public

2026-07-30 00:00

Credits

Argus Systems - ByteRay Ltd.

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-71967",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-10T18:58:32.879110Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-10T21:10:24.782Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "affected",
          "packageURL": "pkg:github/OP-TEE/optee_os",
          "product": "optee_os",
          "repo": "https://github.com/OP-TEE/optee_os",
          "vendor": "OP-TEE",
          "versions": [
            {
              "lessThanOrEqual": "4.10.0",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "0aadfc23407f50e770eb5ddd871fc208f5626833",
              "versionType": "git"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
            {
              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:o:op-tee:op-tee_os:*:*:*:*:*:*:*:*",
                  "versionEndIncluding": "4.10.0",
                  "vulnerable": true
                }
              ],
              "negate": false,
              "operator": "OR"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Argus Systems - ByteRay Ltd."
        }
      ],
      "datePublic": "2026-07-30T00:00:00.000Z",
      "descriptions": [
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          "lang": "en",
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        }
      ],
      "metrics": [
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          "cvssV4_0": {
            "Automatable": "NOT_DEFINED",
            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
            "attackComplexity": "LOW",
            "attackRequirements": "PRESENT",
            "attackVector": "LOCAL",
            "baseScore": 5.7,
            "baseSeverity": "MEDIUM",
            "exploitMaturity": "NOT_DEFINED",
            "privilegesRequired": "LOW",
            "providerUrgency": "NOT_DEFINED",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "HIGH",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
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            "attackVector": "LOCAL",
            "availabilityImpact": "HIGH",
            "baseScore": 5.5,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "UNCHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
            "version": "3.1"
          },
          "format": "CVSS",
          "scenarios": [
            {
              "lang": "en",
              "value": "GENERAL"
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          ]
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
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              "lang": "en",
              "type": "CWE"
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      "providerMetadata": {
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      "references": [
        {
          "name": "Pull Request",
          "tags": [
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          "url": "https://github.com/OP-TEE/optee_os/pull/7899"
        },
        {
          "name": "Patch Commit",
          "tags": [
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          "url": "https://github.com/OP-TEE/optee_os/commit/0aadfc23407f50e770eb5ddd871fc208f5626833"
        },
        {
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          "url": "https://www.vulncheck.com/advisories/op-tee-os-null-pointer-dereference-dos-via-widevine-pta-open-session"
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      "tags": [
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      "title": "OP-TEE OS 4.10.0 NULL Pointer Dereference DoS via Widevine PTA open_session",
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      }
    }
  },
  "cveMetadata": {
    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-71967",
    "datePublished": "2026-08-10T18:11:01.124Z",
    "dateReserved": "2026-08-08T16:43:04.178Z",
    "dateUpdated": "2026-08-14T16:51:53.677Z",
    "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.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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.

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UBUNTU-CVE-2026-71967 (CVE-2026-71967)

CVE-2026-71967 (GCVE-0-2026-71967)

Tags

Sightings

Nomenclature

Related by attack behaviour