CVE-2026-33797

An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific genuine BGP packet in an already established BGP session to reset only that session causing a Denial of Service (DoS). An attacker repeatedly sending the packet will sustain the Denial of Service (DoS).This issue affects Junos OS: * 25.2 versions before 25.2R2 This issue does not affect Junos OS versions before 25.2R1. This issue affects Junos OS Evolved: * 25.2-EVO versions before 25.2R2-EVO This issue does not affect Junos OS Evolved versions before 25.2R1-EVO. eBGP and iBGP are affected. IPv4 and IPv6 are affected.

CVSS v3 7.4 HIGH

7.4^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.0

Attack Vector ADJACENT_NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope CHANGED

References

Link	Resource
https://kb.juniper.net/JSA107850	Vendor Advisory
https://supportportal.juniper.net/JSA107850

Configurations

Configuration 1 (hide)

OR	cpe:2.3:o:juniper:junos:25.2:-::::::
	cpe:2.3:o:juniper:junos:25.2:r1::::::
	cpe:2.3:o:juniper:junos:25.2:r1-s1::::::
	cpe:2.3:o:juniper:junos:25.2:r1-s2::::::
	cpe:2.3:o:juniper:junos_os_evolved:25.2:-::::::
	cpe:2.3:o:juniper:junos_os_evolved:25.2:r1::::::
	cpe:2.3:o:juniper:junos_os_evolved:25.2:r1-s1::::::
	cpe:2.3:o:juniper:junos_os_evolved:25.2:r1-s2::::::

History

No history.

Information

Published : 2026-04-09 22:16

Updated : 2026-06-17 10:38

NVD link : CVE-2026-33797

Mitre link : CVE-2026-33797

CVE.ORG link : CVE-2026-33797

JSON object : View

Products Affected

juniper

junos_os_evolved
junos

CWE

CWE-20

Improper Input Validation

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"modifiedPrivilegesRequired": "NOT_DEFINED", "modifiedSubIntegrityImpact": "NOT_DEFINED", "modifiedVulnIntegrityImpact": "NOT_DEFINED", "vulnerabilityResponseEffort": "MODERATE", "modifiedSubAvailabilityImpact": "NOT_DEFINED", "modifiedVulnAvailabilityImpact": "NOT_DEFINED", "modifiedSubConfidentialityImpact": "NOT_DEFINED", "modifiedVulnConfidentialityImpact": "NOT_DEFINED"}}]}, "affected": [{"source": "sirt@juniper.net", "affectedData": [{"vendor": "Juniper Networks", "product": "Junos OS", "versions": [{"status": "affected", "version": "25.2", "lessThan": "25.2R2", "versionType": "semver"}, {"status": "unaffected", "version": "0", "lessThan": "25.2R1", "versionType": "semver"}], "defaultStatus": "unaffected"}, {"vendor": "Juniper Networks", "modules": ["bgp"], "product": "Junos OS Evolved", "versions": [{"status": "affected", "version": "25.2", "lessThan": "25.2R2-EVO", "versionType": "semver"}, {"status": "unaffected", "version": "0", "lessThan": "25.2R1-EVO", "versionType": "semver"}], "defaultStatus": "unaffected"}]}], "published": "2026-04-09T22:16:29.547", "references": [{"url": "https://kb.juniper.net/JSA107850", "tags": ["Vendor Advisory"], "source": "sirt@juniper.net"}, {"url": "https://supportportal.juniper.net/JSA107850", "source": "sirt@juniper.net"}], "vulnStatus": "Modified", "weaknesses": [{"type": "Secondary", "source": "sirt@juniper.net", "description": [{"lang": "en", "value": "CWE-20"}]}], "descriptions": [{"lang": "en", "value": "An Improper Input Validation vulnerability in Juniper Networks Junos OS and Junos OS Evolved allows an unauthenticated, adjacent attacker, sending a specific genuine BGP packet in an already established BGP session to reset only that session causing a Denial of Service (DoS).\n\nAn attacker repeatedly sending the packet will sustain the Denial of Service (DoS).This issue affects Junos OS:\n\n * 25.2 versions before 25.2R2\n\n\nThis issue does not affect Junos OS versions before 25.2R1.\n\nThis issue affects Junos OS Evolved: \n * 25.2-EVO versions before 25.2R2-EVO\n\n\nThis issue does not affect Junos OS Evolved versions before 25.2R1-EVO.\n\neBGP and iBGP are affected.\nIPv4 and IPv6 are affected."}], "lastModified": "2026-06-17T10:38:07.160", "configurations": [{"nodes": [{"negate": false, "cpeMatch": [{"criteria": "cpe:2.3:o:juniper:junos:25.2:-:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "1B7572BB-9C77-4214-9C5F-CC83C7B93E37"}, {"criteria": "cpe:2.3:o:juniper:junos:25.2:r1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "CAADBF98-38BE-40E2-AF1B-9077DCED0809"}, {"criteria": "cpe:2.3:o:juniper:junos:25.2:r1-s1:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "558F0A4C-0C72-4BF1-B2DE-C0D3BFD54BCD"}, {"criteria": "cpe:2.3:o:juniper:junos:25.2:r1-s2:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": "127FE528-AB27-4B18-AF3B-1BE7C0AEEE20"}, {"criteria": "cpe:2.3:o:juniper:junos_os_evolved:25.2:-:*:*:*:*:*:*", "vulnerable": true, "matchCriteriaId": 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