GCVE Workshop - 22 September 2026 (14:00-18:00), Luxembourg Before The Vulnopticon Conference - Registration

CVE-2026-53671 (GCVE-0-2026-53671)

Vulnerability from cvelistv5 – Published: 2026-09-02 17:54 – Updated: 2026-09-05 01:00
VLAI
Title
PREVAIL: Context-write no-op in do_mem_store allows unsafe eBPF programs to pass verification
Summary
PREVAIL is a Polynomial-Runtime EBPF Verifier using an Abstract Interpretation Layer. Prior to version 0.2.4, the abstract transformer in prevail treats writes through a T_CTX-typed base register as a silent no-op: do_mem_store in src/crab/ebpf_transformer.cpp only models T_STACK stores, and the checker's T_CTX bounds arm never tests AccessType::write. An attacker can craft an eBPF program that overwrites a context field (e.g., ctx->data), reload that field typed as T_PACKET, and dereference an attacker-controlled address — and prevail will report the program as safe. This issue has been patched in version 0.2.4.
SSVC
Exploitation: poc Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-05 00:59 UTC
CWE
Impacted products
Vendor Product Version CPE status
vbpf prevail Affected: < 0.2.4
guessed Create a notification for this product.
Show details on NVD website

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-53671",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-05T00:59:35.326258Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-05T01:00:30.688Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/vbpf/prevail/security/advisories/GHSA-65rv-h458-cq99"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "prevail",
          "vendor": "vbpf",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.2.4"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "PREVAIL is a Polynomial-Runtime EBPF Verifier using an Abstract Interpretation Layer. Prior to version 0.2.4, the abstract transformer in prevail treats writes through a T_CTX-typed base register as a silent no-op: do_mem_store in src/crab/ebpf_transformer.cpp only models T_STACK stores, and the checker\u0027s T_CTX bounds arm never tests AccessType::write. An attacker can craft an eBPF program that overwrites a context field (e.g., ctx-\u003edata), reload that field typed as T_PACKET, and dereference an attacker-controlled address \u2014 and prevail will report the program as safe. This issue has been patched in version 0.2.4."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 9.3,
            "baseSeverity": "CRITICAL",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "HIGH",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-682",
              "description": "CWE-682: Incorrect Calculation",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-02T17:54:30.682Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/vbpf/prevail/security/advisories/GHSA-65rv-h458-cq99",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/vbpf/prevail/security/advisories/GHSA-65rv-h458-cq99"
        },
        {
          "name": "https://github.com/vbpf/prevail/commit/de65234f67d2608b54d12571edb585ead224363c",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/vbpf/prevail/commit/de65234f67d2608b54d12571edb585ead224363c"
        },
        {
          "name": "https://github.com/vbpf/prevail/releases/tag/v0.2.4",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/vbpf/prevail/releases/tag/v0.2.4"
        }
      ],
      "source": {
        "advisory": "GHSA-65rv-h458-cq99",
        "discovery": "UNKNOWN"
      },
      "title": "PREVAIL: Context-write no-op in do_mem_store allows unsafe eBPF programs to pass verification"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-53671",
    "datePublished": "2026-09-02T17:54:30.682Z",
    "dateReserved": "2026-06-09T20:50:36.878Z",
    "dateUpdated": "2026-09-05T01:00:30.688Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "epss": {
      "cve": "CVE-2026-53671",
      "date": "2026-09-04",
      "epss": "0.00291",
      "percentile": "0.21316"
    },
    "nvd": "{\"cve\":{\"id\":\"CVE-2026-53671\",\"sourceIdentifier\":\"security-advisories@github.com\",\"published\":\"2026-09-02T18:20:00.293\",\"lastModified\":\"2026-09-05T01:16:48.910\",\"vulnStatus\":\"Received\",\"cveTags\":[],\"descriptions\":[{\"lang\":\"en\",\"value\":\"PREVAIL is a Polynomial-Runtime EBPF Verifier using an Abstract Interpretation Layer. Prior to version 0.2.4, the abstract transformer in prevail treats writes through a T_CTX-typed base register as a silent no-op: do_mem_store in src/crab/ebpf_transformer.cpp only models T_STACK stores, and the checker\u0027s T_CTX bounds arm never tests AccessType::write. An attacker can craft an eBPF program that overwrites a context field (e.g., ctx-\u003edata), reload that field typed as T_PACKET, and dereference an attacker-controlled address \u2014 and prevail will report the program as safe. This issue has been patched in version 0.2.4.\"}],\"affected\":[{\"source\":\"security-advisories@github.com\",\"affectedData\":[{\"vendor\":\"vbpf\",\"product\":\"prevail\",\"versions\":[{\"version\":\"\u003c 0.2.4\",\"status\":\"affected\"}]}]}],\"metrics\":{\"cvssMetricV40\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"cvssData\":{\"version\":\"4.0\",\"vectorString\":\"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/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\",\"baseScore\":9.3,\"baseSeverity\":\"CRITICAL\",\"attackVector\":\"NETWORK\",\"attackComplexity\":\"LOW\",\"attackRequirements\":\"NONE\",\"privilegesRequired\":\"NONE\",\"userInteraction\":\"NONE\",\"vulnConfidentialityImpact\":\"HIGH\",\"vulnIntegrityImpact\":\"HIGH\",\"vulnAvailabilityImpact\":\"NONE\",\"subConfidentialityImpact\":\"NONE\",\"subIntegrityImpact\":\"NONE\",\"subAvailabilityImpact\":\"NONE\",\"exploitMaturity\":\"NOT_DEFINED\",\"confidentialityRequirement\":\"NOT_DEFINED\",\"integrityRequirement\":\"NOT_DEFINED\",\"availabilityRequirement\":\"NOT_DEFINED\",\"modifiedAttackVector\":\"NOT_DEFINED\",\"modifiedAttackComplexity\":\"NOT_DEFINED\",\"modifiedAttackRequirements\":\"NOT_DEFINED\",\"modifiedPrivilegesRequired\":\"NOT_DEFINED\",\"modifiedUserInteraction\":\"NOT_DEFINED\",\"modifiedVulnConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedVulnIntegrityImpact\":\"NOT_DEFINED\",\"modifiedVulnAvailabilityImpact\":\"NOT_DEFINED\",\"modifiedSubConfidentialityImpact\":\"NOT_DEFINED\",\"modifiedSubIntegrityImpact\":\"NOT_DEFINED\",\"modifiedSubAvailabilityImpact\":\"NOT_DEFINED\",\"Safety\":\"NOT_DEFINED\",\"Automatable\":\"NOT_DEFINED\",\"Recovery\":\"NOT_DEFINED\",\"valueDensity\":\"NOT_DEFINED\",\"vulnerabilityResponseEffort\":\"NOT_DEFINED\",\"providerUrgency\":\"NOT_DEFINED\"}}],\"ssvcV203\":[{\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\",\"ssvcData\":{\"timestamp\":\"2026-09-05T00:59:35.326258Z\",\"id\":\"CVE-2026-53671\",\"options\":[{\"exploitation\":\"poc\"},{\"automatable\":\"yes\"},{\"technicalImpact\":\"total\"}],\"role\":\"CISA Coordinator\",\"version\":\"2.0.3\"}}]},\"weaknesses\":[{\"source\":\"security-advisories@github.com\",\"type\":\"Secondary\",\"description\":[{\"lang\":\"en\",\"value\":\"CWE-682\"}]}],\"references\":[{\"url\":\"https://github.com/vbpf/prevail/commit/de65234f67d2608b54d12571edb585ead224363c\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/vbpf/prevail/releases/tag/v0.2.4\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/vbpf/prevail/security/advisories/GHSA-65rv-h458-cq99\",\"source\":\"security-advisories@github.com\"},{\"url\":\"https://github.com/vbpf/prevail/security/advisories/GHSA-65rv-h458-cq99\",\"source\":\"134c704f-9b21-4f2e-91b3-4a467353bcc0\"}]}}",
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-53671\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"poc\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-09-05T00:59:35.326258Z\"}}}], \"references\": [{\"url\": \"https://github.com/vbpf/prevail/security/advisories/GHSA-65rv-h458-cq99\", \"tags\": [\"exploit\"]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-09-05T01:00:08.555Z\"}}], \"cna\": {\"title\": \"PREVAIL: Context-write no-op in do_mem_store allows unsafe eBPF programs to pass verification\", \"source\": {\"advisory\": \"GHSA-65rv-h458-cq99\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV4_0\": {\"version\": \"4.0\", \"baseScore\": 9.3, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"CRITICAL\", \"vectorString\": \"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"attackRequirements\": \"NONE\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"HIGH\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"NONE\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"HIGH\"}}], \"affected\": [{\"vendor\": \"vbpf\", \"product\": \"prevail\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003c 0.2.4\"}]}], \"references\": [{\"url\": \"https://github.com/vbpf/prevail/security/advisories/GHSA-65rv-h458-cq99\", \"name\": \"https://github.com/vbpf/prevail/security/advisories/GHSA-65rv-h458-cq99\", \"tags\": [\"x_refsource_CONFIRM\"]}, {\"url\": \"https://github.com/vbpf/prevail/commit/de65234f67d2608b54d12571edb585ead224363c\", \"name\": \"https://github.com/vbpf/prevail/commit/de65234f67d2608b54d12571edb585ead224363c\", \"tags\": [\"x_refsource_MISC\"]}, {\"url\": \"https://github.com/vbpf/prevail/releases/tag/v0.2.4\", \"name\": \"https://github.com/vbpf/prevail/releases/tag/v0.2.4\", \"tags\": [\"x_refsource_MISC\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"PREVAIL is a Polynomial-Runtime EBPF Verifier using an Abstract Interpretation Layer. Prior to version 0.2.4, the abstract transformer in prevail treats writes through a T_CTX-typed base register as a silent no-op: do_mem_store in src/crab/ebpf_transformer.cpp only models T_STACK stores, and the checker\u0027s T_CTX bounds arm never tests AccessType::write. An attacker can craft an eBPF program that overwrites a context field (e.g., ctx-\u003edata), reload that field typed as T_PACKET, and dereference an attacker-controlled address \\u2014 and prevail will report the program as safe. This issue has been patched in version 0.2.4.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-682\", \"description\": \"CWE-682: Incorrect Calculation\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-09-02T17:54:30.682Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-53671\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-09-05T01:00:30.688Z\", \"dateReserved\": \"2026-06-09T20:50:36.878Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-09-02T17:54:30.682Z\", \"assignerShortName\": \"GitHub_M\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

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.

Loading…

Detection rules are retrieved from Rulezet.

Loading…

Loading…

Loading…