CVE-2026-44498 (GCVE-0-2026-44498)

Vulnerability from cvelistv5 – Published: 2026-05-08 15:09 – Updated: 2026-05-08 15:09
VLAI?
Title
ZEBRA: Block Validator Undercounts Coinbase and P2SH Sigops
Summary
ZEBRA is a Zcash node written entirely in Rust. Prior to version 4.4.0, Zebra's block validator undercounts transparent signature operations against the 20000-sigop block limit (MAX_BLOCK_SIGOPS), allowing it to accept blocks that zcashd rejects with bad-blk-sigops. A miner who produces such a block can split the network: Zebra nodes follow the offending chain while zcashd nodes do not. This issue has been patched in version 4.4.0.
Severity ?
9.2 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N
CWE
Assigner
References
Impacted products
Vendor Product Version
ZcashFoundation zebra Affected: < 4.4.0
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          "versions": [
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        }
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            "privilegesRequired": "NONE",
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            "subConfidentialityImpact": "NONE",
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            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:H/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "HIGH"
          }
        }
      ],
      "problemTypes": [
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          "descriptions": [
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              "description": "CWE-682: Incorrect Calculation",
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            }
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      "providerMetadata": {
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        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
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        },
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          "tags": [
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        }
      ],
      "source": {
        "advisory": "GHSA-jv4h-j224-23cc",
        "discovery": "UNKNOWN"
      },
      "title": "ZEBRA: Block Validator Undercounts Coinbase and P2SH Sigops"
    }
  },
  "cveMetadata": {
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    "dateReserved": "2026-05-06T18:28:20.886Z",
    "dateUpdated": "2026-05-08T15:09:09.919Z",
    "state": "PUBLISHED"
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  }
}


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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

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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.