{"dataType": "CVE_RECORD", "dataVersion": "5.2", "cveMetadata": {"cveId": "CVE-2026-21920", "assignerOrgId": "8cbe9d5a-a066-4c94-8978-4b15efeae968", "state": "PUBLISHED", "assignerShortName": "juniper", "dateReserved": "2026-01-05T17:32:48.712Z", "datePublished": "2026-01-15T20:28:10.526Z", "dateUpdated": "2026-01-15T20:59:21.070Z"}, "containers": {"cna": {"affected": [{"defaultStatus": "unaffected", "platforms": ["SRX Series"], "product": "Junos OS", "vendor": "Juniper Networks", "versions": [{"lessThan": "23.4R2-S5", "status": "affected", "version": "23.4", "versionType": "semver"}, {"lessThan": "24.2R2-S1", "status": "affected", "version": "24.2", "versionType": "semver"}, {"lessThan": "24.4R2", "status": "affected", "version": "24.4", "versionType": "semver"}, {"lessThan": "23.4R1", "status": "unaffected", "version": "0", "versionType": "semver"}]}], "configurations": [{"lang": "en", "supportingMedia": [{"base64": false, "type": "text/html", "value": "<span 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"CISA ADP Vulnrichment", "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-01-15T20:59:21.070Z"}}]}}

{"dataType": "CVE_RECORD", "containers": {"adp": [{"title": "CISA ADP Vulnrichment", "metrics": [{"other": {"type": "ssvc", "content": {"id": "CVE-2026-21920", "role": "CISA Coordinator", "options": [{"Exploitation": "none"}, {"Automatable": "yes"}, {"Technical Impact": "partial"}], "version": "2.0.3", "timestamp": "2026-01-15T20:58:50.543674Z"}}}], "providerMetadata": {"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0", "shortName": "CISA-ADP", "dateUpdated": "2026-01-15T20:59:08.031Z"}}], "cna": {"title": "Junos OS: SRX Series: If a specific request is processed by the DNS subsystem flowd will crash", "source": {"defect": ["1851909"], "advisory": "JSA106020", "discovery": "USER"}, "metrics": [{"format": "CVSS", "cvssV3_1": {"scope": "UNCHANGED", "version": "3.1", "baseScore": 7.5, "attackVector": "NETWORK", "baseSeverity": "HIGH", "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H", "integrityImpact": "NONE", "userInteraction": "NONE", "attackComplexity": "LOW", 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resolve this specific issue: 23.4R2-S5, 24.2R2-S1, 24.4R2, 24.4R2-S1, 25.2R1, and all subsequent releases.", "base64": false}]}], "datePublic": "2026-01-14T17:00:00.000Z", "references": [{"url": "https://supportportal.juniper.net/JSA106020", "tags": ["vendor-advisory"]}, {"url": "https://kb.juniper.net/JSA106020", "tags": ["vendor-advisory"]}], "workarounds": [{"lang": "en", "value": "There are no known workarounds for this issue.", "supportingMedia": [{"type": "text/html", "value": "There are no known workarounds for this issue.", "base64": false}]}], "x_generator": {"engine": "Vulnogram 0.1.0-dev"}, "descriptions": [{"lang": "en", "value": "An Unchecked Return Value vulnerability in the DNS module of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).\n\n\n\n\nIf an SRX Series device configured for DNS processing, receives a specifically formatted DNS request flowd will crash and restart, which causes a service interruption until the process has recovered.\n\nThis issue affects Junos OS on SRX Series:\n\n\n\n * 23.4 versions before 23.4R2-S5,\n * 24.2 versions before 24.2R2-S1,\n * 24.4 versions before 24.4R2.\n\n\n\n\n\n\nThis issue does not affect Junos OS versions before 23.4R1.", "supportingMedia": [{"type": "text/html", "value": "<span style=\"background-color: rgb(255, 255, 255);\">An Unchecked Return Value vulnerability in the DNS module of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS).</span><br>\n\n<br><br>If an SRX Series device configured for DNS processing, receives a specifically formatted DNS request flowd will crash and restart, which causes a service interruption until the process has recovered.<br><br><p>This issue affects Junos OS on SRX Series:</p><p></p><ul><li>23.4 versions before 23.4R2-S5,</li><li>24.2 versions before 24.2R2-S1,</li><li>24.4 versions before 24.4R2.</li></ul><p></p>\n\n<p>This issue does not affect Junos OS versions before 23.4R1.</p>", "base64": false}]}], "problemTypes": [{"descriptions": [{"lang": "en", "type": "CWE", "cweId": "CWE-252", "description": "CWE-252 Unchecked Return Value"}]}], "configurations": [{"lang": "en", "value": "A device is exposed to this issue when one of the following features are used / configurations are present:\n\n- GeoIP:\n\n[ security dynamic-address address-name <name> profile category GeoIP ... ]\n\n\n- DNS security:\n\n[\u00a0services security-metadata-streaming policy <name> dns detections ... ]\n\nor\n\n[ services security-intelligence profile <profile-name> category DNS ]\n[ services security-intelligence profile policy <policy-name> DNS <profile-name> ]", "supportingMedia": [{"type": "text/html", "value": "<span style=\"background-color: rgb(255, 255, 255);\">A device is exposed to this issue when one of the following features are used / configurations are present:<br><br>- GeoIP:<br></span><tt><tt><tt></tt><br><tt><span style=\"background-color: rgb(255, 255, 255);\">[ security dynamic-address address-name &lt;name&gt; profile category GeoIP ... ]<br></span></tt></tt></tt><br><br>- DNS security:<br><br><tt><tt><tt><span style=\"background-color: rgb(255, 255, 255);\">[&nbsp;services security-metadata-streaming policy &lt;name&gt; dns detections ... ]<br><br>or<br><br>[ services security-intelligence profile &lt;profile-name&gt; category DNS ]<br>[ services security-intelligence profile policy &lt;policy-name&gt; DNS &lt;profile-name&gt; ]<br></span></tt><tt><tt><tt><br><tt>\n\n</tt></tt></tt><tt></tt><tt></tt><tt></tt><tt></tt><tt></tt><tt></tt></tt></tt></tt><tt></tt>", "base64": false}]}], "providerMetadata": {"orgId": "8cbe9d5a-a066-4c94-8978-4b15efeae968", "shortName": "juniper", "dateUpdated": "2026-01-15T20:28:10.526Z"}}}, "cveMetadata": {"cveId": "CVE-2026-21920", "state": "PUBLISHED", "dateUpdated": "2026-01-15T20:59:21.070Z", "dateReserved": "2026-01-05T17:32:48.712Z", "assignerOrgId": "8cbe9d5a-a066-4c94-8978-4b15efeae968", "datePublished": "2026-01-15T20:28:10.526Z", "assignerShortName": "juniper"}, "dataVersion": "5.2"}

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