Vulnerability-Lookup

CVE-2026-34987 (GCVE-0-2026-34987)

Vulnerability from cvelistv5 – Published: 2026-04-09 18:48 – Updated: 2026-04-10 14:12

Title

Wasmtime with Winch compiler backend on aarch64 may allow a sandbox-escaping memory access

Summary

Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime with its Winch (baseline) non-default compiler backend may allow properly constructed guest Wasm to access host memory outside of its linear-memory sandbox. This vulnerability requires use of the Winch compiler (-Ccompiler=winch). By default, Wasmtime uses its Cranelift backend, not Winch. With Winch, the same incorrect assumption is present in theory on both aarch64 and x86-64. The aarch64 case has an observed-working proof of concept, while the x86-64 case is theoretical and may not be reachable in practice. This Winch compiler bug can allow the Wasm guest to access memory before or after the linear-memory region, independently of whether pre- or post-guard regions are configured. The accessible range in the initial bug proof-of-concept is up to 32KiB before the start of memory, or ~4GiB after the start of memory, independently of the size of pre- or post-guard regions or the use of explicit or guard-region-based bounds checking. However, the underlying bug assumes a 32-bit memory offset stored in a 64-bit register has its upper bits cleared when it may not, and so closely related variants of the initial proof-of-concept may be able to access truly arbitrary memory in-process. This could result in a host process segmentation fault (DoS), an arbitrary data leak from the host process, or with a write, potentially an arbitrary RCE. This vulnerability is fixed in 36.0.7, 42.0.2, and 43.0.1.

Severity

9 (Critical)


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

SSVC

Exploitation: none Automatable: no Technical Impact: total

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-10 14:12 UTC

CWE

CWE-125 - Out-of-bounds Read
CWE-787 - Out-of-bounds Write

Assigner

GitHub_M mitre root

References

1 reference

URL	Tags
https://github.com/bytecodealliance/wasmtime/secu…	x_refsource_CONFIRM

Impacted products

1 product

Vendor	Product	Version	CPE status
bytecodealliance	wasmtime	Affected: >= 25.0.0, < 36.0.7 Affected: >= 37.0.0, < 42.0.2 Affected: >= 43.0.0, < 44.0.1	guessed

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JSON

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FKIE_CVE-2026-34987

Vulnerability from fkie_nvd - Published: 2026-04-09 19:16 - Updated: 2026-06-17 10:39

Severity

9.9 (Critical) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

Summary

References

	URL	Tags
	security-advisories@github.com	https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-xx5w-cvp6-jv83	Vendor Advisory

Impacted products

Vendor	Product	Version
bytecodealliance	wasmtime	*
bytecodealliance	wasmtime	*
bytecodealliance	wasmtime	43.0.0

JSON

To clipboard

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              "criteria": "cpe:2.3:a:bytecodealliance:wasmtime:43.0.0:*:*:*:*:rust:*:*",
              "matchCriteriaId": "9AD0150A-FE79-4EA6-995B-8CAFC7F246B5",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime with its Winch (baseline) non-default compiler backend may allow properly constructed guest Wasm to access host memory outside of its linear-memory sandbox. This vulnerability requires use of the Winch compiler (-Ccompiler=winch). By default, Wasmtime uses its Cranelift backend, not Winch. With Winch, the same incorrect assumption is present in theory on both aarch64 and x86-64. The aarch64 case has an observed-working proof of concept, while the x86-64 case is theoretical and may not be reachable in practice. This Winch compiler bug can allow the Wasm guest to access memory before or after the linear-memory region, independently of whether pre- or post-guard regions are configured. The accessible range in the initial bug proof-of-concept is up to 32KiB before the start of memory, or ~4GiB after the start of memory, independently of the size of pre- or post-guard regions or the use of explicit or guard-region-based bounds checking. However, the underlying bug assumes a 32-bit memory offset stored in a 64-bit register has its upper bits cleared when it may not, and so closely related variants of the initial proof-of-concept may be able to access truly arbitrary memory in-process. This could result in a host process segmentation fault (DoS), an arbitrary data leak from the host process, or with a write, potentially an arbitrary RCE. This vulnerability is fixed in 36.0.7, 42.0.2, and 43.0.1."
    }
  ],
  "id": "CVE-2026-34987",
  "lastModified": "2026-06-17T10:39:56.833",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 9.9,
          "baseSeverity": "CRITICAL",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "LOW",
          "scope": "CHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.1,
        "impactScore": 6.0,
        "source": "nvd@nist.gov",
        "type": "Primary"
      }
    ],
    "cvssMetricV40": [
      {
        "cvssData": {
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "PRESENT",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 9.0,
          "baseSeverity": "CRITICAL",
          "confidentialityRequirement": "NOT_DEFINED",
          "exploitMaturity": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "privilegesRequired": "LOW",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "HIGH",
          "subIntegrityImpact": "HIGH",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "HIGH",
          "vulnConfidentialityImpact": "HIGH",
          "vulnIntegrityImpact": "HIGH",
          "vulnerabilityResponseEffort": "NOT_DEFINED"
        },
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-34987",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-04-10T14:12:37.362283Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-04-09T19:16:25.000",
  "references": [
    {
      "source": "security-advisories@github.com",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-xx5w-cvp6-jv83"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
        },
        {
          "lang": "en",
          "value": "CWE-787"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}

GHSA-XX5W-CVP6-JV83

Vulnerability from github – Published: 2026-04-10 15:31 – Updated: 2026-04-10 15:31

Summary

Wasmtime with Winch compiler backend on aarch64 may allow a sandbox-escaping memory access

Details

Impact

Wasmtime with its Winch (baseline) non-default compiler backend may allow properly constructed guest Wasm to access host memory outside of its linear-memory sandbox.

This vulnerability requires use of the Winch compiler (-Ccompiler=winch). By default, Wasmtime uses its Cranelift backend, not Winch. With Winch, the same incorrect assumption is present in theory on both aarch64 and x86-64. The aarch64 case has an observed-working proof of concept, while the x86-64 case is theoretical and may not be reachable in practice.

This Winch compiler bug can allow the Wasm guest to access memory before or after the linear-memory region, independently of whether pre- or post-guard regions are configured. The accessible range in the initial bug proof-of-concept is up to 32KiB before the start of memory, or ~4GiB after the start of memory, independently of the size of pre- or post-guard regions or the use of explicit or guard-region-based bounds checking. However, the underlying bug assumes a 32-bit memory offset stored in a 64-bit register has its upper bits cleared when it may not, and so closely related variants of the initial proof-of-concept may be able to access truly arbitrary memory in-process. This could result in a host process segmentation fault (DoS), an arbitrary data leak from the host process, or with a write, potentially an arbitrary RCE.

Patches

Wasmtime 43.0.1, 42.0.2, and 36.0.7 have been released with fixes for this issue.

Workaround

There are no workarounds within the Winch compiler backend while using the affected versions. Users of Wasmtime are encouraged either to upgrade to patched versions or, if that is not possible, use the Cranelift compiler backend.

Severity

9.2 (Critical)


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

Show details on source website

JSON

To clipboard

{
  "affected": [
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "wasmtime"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "25.0.0"
            },
            {
              "fixed": "36.0.7"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "wasmtime"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "37.0.0"
            },
            {
              "fixed": "42.0.2"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "package": {
        "ecosystem": "crates.io",
        "name": "wasmtime"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "43.0.0"
            },
            {
              "fixed": "43.0.1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "43.0.0"
      ]
    }
  ],
  "aliases": [
    "CVE-2026-34987"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-125",
      "CWE-787"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-04-10T15:31:18Z",
    "nvd_published_at": "2026-04-09T19:16:25Z",
    "severity": "CRITICAL"
  },
  "details": "### Impact\n\nWasmtime with its Winch (baseline) non-default compiler backend may allow properly constructed guest Wasm to access host memory outside of its linear-memory sandbox.\n\nThis vulnerability requires use of the Winch compiler (`-Ccompiler=winch`). By default, Wasmtime uses its Cranelift backend, not Winch. With Winch, the same incorrect assumption is present in theory on both aarch64 and x86-64. The aarch64 case has an observed-working proof of concept, while the x86-64 case is theoretical and may not be reachable in practice.\n\nThis Winch compiler bug can allow the Wasm guest to access memory before or after the linear-memory region, independently of whether pre- or post-guard regions are configured. The accessible range in the initial bug proof-of-concept is up to 32KiB before the start of memory, or ~4GiB after the start of memory, independently of the size of pre- or post-guard regions or the use of explicit or guard-region-based bounds checking. However, the underlying bug assumes a 32-bit memory offset stored in a 64-bit register has its upper bits cleared when it may not, and so closely related variants of the initial proof-of-concept may be able to access truly arbitrary memory in-process. This could result in a host process segmentation fault (DoS), an arbitrary data leak from the host process, or with a write, potentially an arbitrary RCE.\n\n### Patches\n\nWasmtime 43.0.1, 42.0.2, and 36.0.7 have been released with fixes for this issue.\n\n### Workaround\n\nThere are no workarounds within the Winch compiler backend while using the affected versions. Users of Wasmtime are encouraged either to upgrade to patched versions or, if that is not possible, use the Cranelift compiler backend.",
  "id": "GHSA-xx5w-cvp6-jv83",
  "modified": "2026-04-10T15:31:18Z",
  "published": "2026-04-10T15:31:18Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-xx5w-cvp6-jv83"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-34987"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/bytecodealliance/wasmtime"
    },
    {
      "type": "WEB",
      "url": "https://rustsec.org/advisories/RUSTSEC-2026-0095.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Wasmtime with Winch compiler backend on aarch64 may allow a sandbox-escaping memory access"
}

OPENSUSE-SU-2026:20749-1

Vulnerability from csaf_opensuse - Published: 2026-05-14 08:07 - Updated: 2026-09-17 17:32

Summary

Security update for tree-sitter

Severity

Important

Scope

10 vulnerabilities in this advisory, including CVE-2026-34987.

CVE-2026-34987

8.5 (High)


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

Recommended: 13 products

Open the full advisory

RUSTSEC-2026-0095 (CVE-2026-34987)

Vulnerability from osv_rustsec – Published: 2026-04-09 12:00 – Updated: 2026-04-09 19:59 – Source website

Summary

Wasmtime with Winch compiler backend may allow a sandbox-escaping memory access

Details

This is an entry in the RustSec database for the Wasmtime security advisory located at https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-xx5w-cvp6-jv83 For more information see the GitHub-hosted security advisory.

Severity

9.0 (Critical)


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

References

URL

Type

	https://crates.io/crates/wasmtime	PACKAGE
	https://rustsec.org/advisories/RUSTSEC-2026-0095.html	ADVISORY
	https://github.com/bytecodealliance/wasmtime/secu…	ADVISORY

JSON

To clipboard

{
  "affected": [
    {
      "database_specific": {
        "categories": [],
        "cvss": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
        "informational": null
      },
      "ecosystem_specific": {
        "affected_functions": null,
        "affects": {
          "arch": [],
          "functions": [],
          "os": []
        }
      },
      "package": {
        "ecosystem": "crates.io",
        "name": "wasmtime",
        "purl": "pkg:cargo/wasmtime"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0.0.0-0"
            },
            {
              "fixed": "36.0.7"
            },
            {
              "introduced": "37.0.0"
            },
            {
              "fixed": "42.0.2"
            },
            {
              "introduced": "43.0.0"
            },
            {
              "fixed": "43.0.1"
            }
          ],
          "type": "SEMVER"
        }
      ],
      "versions": []
    }
  ],
  "aliases": [
    "CVE-2026-34987",
    "GHSA-xx5w-cvp6-jv83"
  ],
  "database_specific": {
    "license": "CC0-1.0"
  },
  "details": "This is an entry in the RustSec database for the Wasmtime security advisory\nlocated at\nhttps://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-xx5w-cvp6-jv83\nFor more information see the GitHub-hosted security advisory.",
  "id": "RUSTSEC-2026-0095",
  "modified": "2026-04-09T19:59:38Z",
  "published": "2026-04-09T12:00:00Z",
  "references": [
    {
      "type": "PACKAGE",
      "url": "https://crates.io/crates/wasmtime"
    },
    {
      "type": "ADVISORY",
      "url": "https://rustsec.org/advisories/RUSTSEC-2026-0095.html"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-xx5w-cvp6-jv83"
    }
  ],
  "related": [],
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Wasmtime with Winch compiler backend may allow a sandbox-escaping memory access"
}

SUSE-SU-2026:21789-1

Vulnerability from csaf_suse - Published: 2026-05-14 08:09 - Updated: 2026-09-16 19:51

Summary

Security update for tree-sitter

Severity

Important

Scope

10 vulnerabilities in this advisory, including CVE-2026-34987.

CVE-2026-34987

8.5 (High)


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

Recommended: 18 products

Open the full advisory

UBUNTU-CVE-2026-34987 (CVE-2026-34987)

Vulnerability from osv_ubuntu – Published: 2026-04-09 19:16 – Updated: 2026-05-20 15:27 – Source website

Details

Severity

9.0 (Critical)


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

9.9 (Critical)


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

N/A (UNKNOWN)


                    
                      medium

References

URL

Type

	https://ubuntu.com/security/CVE-2026-34987	REPORT
	https://www.cve.org/CVERecord?id=CVE-2026-34987	REPORT
	https://github.com/bytecodealliance/wasmtime/secu…	REPORT

JSON

To clipboard

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "librust-cranelift-dev",
            "binary_version": "0.103.0+16.0.0+dfsg-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:24.04:LTS",
        "name": "rust-wasmtime",
        "purl": "pkg:deb/ubuntu/rust-wasmtime@16.0.0+dfsg-3?arch=source\u0026distro=noble"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "10.0.1+dfsg-7",
        "15.0.1+dfsg-4",
        "16.0.0+dfsg-2",
        "16.0.0+dfsg-3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "librust-cranelift-dev",
            "binary_version": "0.113.1+26.0.1+dfsg-3"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:25.10",
        "name": "rust-wasmtime",
        "purl": "pkg:deb/ubuntu/rust-wasmtime@26.0.1+dfsg-3?arch=source\u0026distro=questing"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "26.0.1+dfsg-3"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "librust-cranelift-dev",
            "binary_version": "0.123.5+36.0.5+dfsg-1"
          }
        ]
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "rust-wasmtime",
        "purl": "pkg:deb/ubuntu/rust-wasmtime@36.0.5+dfsg-1?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "26.0.1+dfsg-3",
        "26.0.1+dfsg-4",
        "28.0.1+dfsg-3",
        "29.0.1+dfsg-5",
        "36.0.5+dfsg-1"
      ]
    }
  ],
  "aliases": [],
  "details": "Wasmtime is a runtime for WebAssembly. From 25.0.0 to before 36.0.7, 42.0.2, and 43.0.1, Wasmtime with its Winch (baseline) non-default compiler backend may allow properly constructed guest Wasm to access host memory outside of its linear-memory sandbox. This vulnerability requires use of the Winch compiler (-Ccompiler=winch). By default, Wasmtime uses its Cranelift backend, not Winch. With Winch, the same incorrect assumption is present in theory on both aarch64 and x86-64. The aarch64 case has an observed-working proof of concept, while the x86-64 case is theoretical and may not be reachable in practice. This Winch compiler bug can allow the Wasm guest to access memory before or after the linear-memory region, independently of whether pre- or post-guard regions are configured. The accessible range in the initial bug proof-of-concept is up to 32KiB before the start of memory, or ~4GiB after the start of memory, independently of the size of pre- or post-guard regions or the use of explicit or guard-region-based bounds checking. However, the underlying bug assumes a 32-bit memory offset stored in a 64-bit register has its upper bits cleared when it may not, and so closely related variants of the initial proof-of-concept may be able to access truly arbitrary memory in-process. This could result in a host process segmentation fault (DoS), an arbitrary data leak from the host process, or with a write, potentially an arbitrary RCE. This vulnerability is fixed in 36.0.7, 42.0.2, and 43.0.1.",
  "id": "UBUNTU-CVE-2026-34987",
  "modified": "2026-05-20T15:27:24Z",
  "published": "2026-04-09T19:16:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-34987"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-34987"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/bytecodealliance/wasmtime/security/advisories/GHSA-xx5w-cvp6-jv83"
    }
  ],
  "related": [],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H",
      "type": "CVSS_V4"
    },
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "medium",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-34987"
  ]
}

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.

Action not permitted

CVE-2026-34987 (GCVE-0-2026-34987)

FKIE_CVE-2026-34987

GHSA-XX5W-CVP6-JV83

Impact

Patches

Workaround

OPENSUSE-SU-2026:20749-1

RUSTSEC-2026-0095 (CVE-2026-34987)

SUSE-SU-2026:21789-1

UBUNTU-CVE-2026-34987 (CVE-2026-34987)

Tags

Sightings

Nomenclature

Related by attack behaviour