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CVE-2020-19861

Status: ModifiedHigh (7.5)—

When a zone file in ldns 1.7.1 is parsed, the function ldns_nsec3_salt_data is too trusted for the length value obtained from the zone file. When the memcpy is copied, the 0xfe - ldns_rdf_size(salt_rdf) byte data can be copied, causing heap overflow information leakage.

CVSS

Exploitation probability (EPSS)

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

Affected technologies (1)

Nlnetlabs — Ldns

CWEs

References

Raw JSON (NVD)

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{
  "id": "CVE-2020-19861",
  "cveTags": [],
  "metrics": {
    "cvssMetricV2": [
      {
        "type": "Primary",
        "source": "nvd@nist.gov",
        "cvssData": {
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          "baseScore": 5,
          "accessVector": "NETWORK",
          "vectorString": "AV:N/AC:L/Au:N/C:P/I:N/A:N",
          "authentication": "NONE",
          "integrityImpact": "NONE",
          "accessComplexity": "LOW",
          "availabilityImpact": "NONE",
          "confidentialityImpact": "PARTIAL"
        },
        "acInsufInfo": false,
        "impactScore": 2.9,
        "baseSeverity": "MEDIUM",
        "obtainAllPrivilege": false,
        "exploitabilityScore": 10,
        "obtainUserPrivilege": false,
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    "cvssMetricV31": [
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          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "integrityImpact": "NONE",
          "userInteraction": "NONE",
          "attackComplexity": "LOW",
          "availabilityImpact": "NONE",
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  "affected": [
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  "published": "2022-01-21T15:15:07.607",
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      "tags": [
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      "source": "af854a3a-2127-422b-91ae-364da2661108"
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  "vulnStatus": "Modified",
  "weaknesses": [
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      "source": "nvd@nist.gov",
      "description": [
        {
          "lang": "en",
          "value": "CWE-125"
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      ]
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  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "When a zone file in ldns 1.7.1 is parsed, the function ldns_nsec3_salt_data is too trusted for the length value obtained from the zone file. When the memcpy is copied, the 0xfe - ldns_rdf_size(salt_rdf) byte data can be copied, causing heap overflow information leakage."
    },
    {
      "lang": "es",
      "value": "Cuando es analizado un archivo de zona en ldns versión 1.7.1, la función ldns_nsec3_salt_data es demasiado confiable para el valor de longitud obtenido del archivo de zona. Cuando es copiado el memcpy, los datos de bytes 0xfe - ldns_rdf_size(salt_rdf) pueden ser copiados, causando un filtrado de información por desbordamiento de pila"
    }
  ],
  "lastModified": "2026-06-17T02:59:59.303",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
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  "sourceIdentifier": "cve@mitre.org"
}