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FKIE_CVE-2026-21917

Vulnerability from fkie_nvd - Published: 2026-01-15 21:16 - Updated: 2026-06-17 10:19
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
An Improper Validation of Syntactic Correctness of Input vulnerability in the Web-Filtering module of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). If an SRX device configured for UTM Web-Filtering receives a specifically malformed SSL packet, this will cause an FPC crash and restart. This issue affects Junos OS on SRX Series: * 23.2 versions from 23.2R2-S2 before 23.2R2-S5,  * 23.4 versions from 23.4R2-S1 before 23.4R2-S5, * 24.2 versions before 24.2R2-S2, * 24.4 versions before 24.4R1-S3, 24.4R2. Earlier versions of Junos are also affected, but no fix is available.
References
sirt@juniper.nethttps://kb.juniper.net/JSA105996Vendor Advisory
sirt@juniper.nethttps://supportportal.juniper.net/JSA105996Vendor Advisory
Impacted products
Vendor Product Version
juniper junos 23.2
juniper junos 23.2
juniper junos 23.2
juniper junos 23.4
juniper junos 23.4
juniper junos 23.4
juniper junos 23.4
juniper junos 24.2
juniper junos 24.2
juniper junos 24.2
juniper junos 24.2
juniper junos 24.2
juniper junos 24.2
juniper junos 24.4
juniper junos 24.4
juniper junos 24.4
juniper junos 24.4
juniper srx1500 -
juniper srx1600 -
juniper srx2300 -
juniper srx300 -
juniper srx320 -
juniper srx340 -
juniper srx345 -
juniper srx380 -
juniper srx4100 -
juniper srx4120 -
juniper srx4200 -
juniper srx4300 -
juniper srx4600 -
juniper srx4700 -
juniper srx5400 -
juniper srx5600 -
juniper srx5800 -
To clipboard 

{
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  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "An Improper Validation of Syntactic Correctness of Input vulnerability in the Web-Filtering module of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).\n\nIf an SRX device configured for UTM Web-Filtering receives a specifically malformed SSL packet, this will cause an FPC crash and restart.\nThis issue affects Junos OS on SRX Series:\n\n\n\n  *  23.2 versions from 23.2R2-S2 before 23.2R2-S5,\u00a0\n  *  23.4 versions from 23.4R2-S1 before 23.4R2-S5,\n  *  24.2 versions before 24.2R2-S2,\n  *  24.4 versions before 24.4R1-S3, 24.4R2.\n\n\nEarlier versions of Junos are also affected, but no fix is available."
    },
    {
      "lang": "es",
      "value": "Una vulnerabilidad de validaci\u00f3n incorrecta de la correcci\u00f3n sint\u00e1ctica de la entrada en el m\u00f3dulo de filtrado web de Juniper Networks Junos OS en la serie SRX permite a un atacante no autenticado y basado en red causar una denegaci\u00f3n de servicio (DoS).\n\nSi un dispositivo SRX configurado para filtrado web UTM recibe un paquete SSL espec\u00edficamente malformado, esto causar\u00e1 un fallo y reinicio del FPC.\nEste problema afecta a Junos OS en la serie SRX:\n\n  *  Versiones 23.2 desde 23.2R2-S2 anteriores a 23.2R2-S5,\n  *  Versiones 23.4 desde 23.4R2-S1 anteriores a 23.4R2-S5,\n  *  Versiones 24.2 anteriores a 24.2R2-S2,\n  *  Versiones 24.4 anteriores a 24.4R1-S3, 24.4R2.\n\nLas versiones anteriores de Junos tambi\u00e9n est\u00e1n afectadas, pero no hay una soluci\u00f3n disponible."
    }
  ],
  "id": "CVE-2026-21917",
  "lastModified": "2026-06-17T10:19:09.490",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
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        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "sirt@juniper.net",
        "type": "Secondary"
      }
    ],
    "cvssMetricV40": [
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        "cvssData": {
          "Automatable": "YES",
          "Recovery": "AUTOMATIC",
          "Safety": "NOT_DEFINED",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "attackVector": "NETWORK",
          "availabilityRequirement": "NOT_DEFINED",
          "baseScore": 8.7,
          "baseSeverity": "HIGH",
          "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": "NONE",
          "providerUrgency": "NOT_DEFINED",
          "subAvailabilityImpact": "LOW",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "userInteraction": "NONE",
          "valueDensity": "NOT_DEFINED",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/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:Y/R:A/V:X/RE:M/U:X",
          "version": "4.0",
          "vulnAvailabilityImpact": "HIGH",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnerabilityResponseEffort": "MODERATE"
        },
        "source": "sirt@juniper.net",
        "type": "Secondary"
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    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-21917",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-01-15T21:12:30.579909Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-01-15T21:16:07.877",
  "references": [
    {
      "source": "sirt@juniper.net",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://kb.juniper.net/JSA105996"
    },
    {
      "source": "sirt@juniper.net",
      "tags": [
        "Vendor Advisory"
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      "url": "https://supportportal.juniper.net/JSA105996"
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  "sourceIdentifier": "sirt@juniper.net",
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-1286"
        }
      ],
      "source": "sirt@juniper.net",
      "type": "Secondary"
    }
  ]
}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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