CVE-2024-21598

Junos OS and Junos OS Evolved: A malformed BGP tunnel encapsulation attribute will lead to an rpd crash

HIGH
7.5
CVSS Score
Published: April 12, 2024 at 02:54 PM UTC
Updated: June 17, 2026 at 07:09 AM UTC
3 products affected across 2 vendorsJunosJunos OS EvolvedJunos OS Evolved

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Severity
HIGH7.5
Exploit prediction
EPSS 0.6%
SSVC
No known exploit

Description

An Improper Validation of Syntactic Correctness of Input vulnerability in the Routing Protocol Daemon (rpd) of Juniper Networks Junos OS and Junos OS Evolved allows a network-based, unauthenticated attacker to cause a Denial of Service (DoS). If a BGP update is received over an established BGP session which contains a tunnel encapsulation attribute with a specifically malformed TLV, rpd will crash and restart. This issue affects Juniper Networks Junos OS: * 20.4 versions 20.4R1 and later versions earlier than 20.4R3-S9; * 21.2 versions earlier than 21.2R3-S7; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3-S5; * 22.1 versions earlier than 22.1R3-S4; * 22.2 versions earlier than 22.2R3-S3; * 22.3 versions earlier than 22.3R3-S1; * 22.4 versions earlier than 22.4R3; * 23.2 versions earlier than 23.2R1-S2, 23.2R2; Junos OS Evolved: * 20.4-EVO versions 20.4R1-EVO and later versions earlier than 20.4R3-S9-EVO; * 21.2-EVO versions earlier than 21.2R3-S7-EVO; * 21.3-EVO versions earlier than 21.3R3-S5-EVO; * 21.4-EVO versions earlier than 21.4R3-S5-EVO; * 22.1-EVO versions earlier than 22.1R3-S4-EVO; * 22.2-EVO versions earlier than 22.2R3-S3-EVO; * 22.3-EVO versions earlier than 22.3R3-S1-EVO; * 22.4-EVO versions earlier than 22.4R3-EVO; * 23.2-EVO versions earlier than 23.2R1-S2-EVO, 23.2R2-EVO; This issue does not affect Juniper Networks * Junos OS versions earlier than 20.4R1; * Junos OS Evolved versions earlier than 20.4R1-EVO. This is a related but separate issue than the one described in JSA79095.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Affected range stops below 20.4r3-s9, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.2r3-s7, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.3r3-s5, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.4r3-s4, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.1r3-s4, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.2r3-s3, so it looks safe — our inference, not a vendor statement
Affected range stops below 20.4R3-S9, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.2R3-S7, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.3R3-S5, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.4R3-S5, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.1R3-S4, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.2R3-S3, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.3R3-S1, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.4R3, so it looks safe — our inference, not a vendor statement
Affected range stops below 23.2R1-S2, 23.2R2, so it looks safe — our inference, not a vendor statement
Affected range stops below 23.2r1-s2, so it looks safe — our inference, not a vendor statement
20.4-EVO ≤ v < 20.4R3-S9-EVO21.2-EVO ≤ v < 21.2R3-S7-EVO21.3-EVO ≤ v < 21.3R3-S5-EVO21.4-EVO ≤ v < 21.4R3-S5-EVO22.1-EVO ≤ v < 22.1R3-S4-EVO22.2-EVO ≤ v < 22.2R3-S3-EVO22.3-EVO ≤ v < 22.3R3-S1-EVO22.4-EVO ≤ v < 22.4R3-EVO23.2-EVO ≤ v < 23.2R1-S2-EVO, 23.2R2-EVO20.4-EVO21.2-EVO21.3-EVO21.4-EVO22.1-EVO22.2-EVO22.3-EVO22.4-EVO23.2-EVO
Affected range stops below 20.4R3-S9-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.2R3-S7-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.3R3-S5-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 21.4R3-S5-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.1R3-S4-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.2R3-S3-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.3R3-S1-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 22.4R3-EVO, so it looks safe — our inference, not a vendor statement
Affected range stops below 23.2R1-S2-EVO, 23.2R2-EVO, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

Patch and advisory references

SSVC — Action Prioritization

SSVCNo known exploitAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.5HIGHjuniper
Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Vector?

Quick Info

StatusANALYZED
CWE
CWE-1286NVD-CWE-Other

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