CVE-2024-21598Network attack vector

Routing daemon crash via malformed BGP tunnel TLV

Published Apr 12, 2024 · Updated Aug 1, 2024

Input-validation failure in Juniper Networks Junos OS and Junos OS Evolved allows remote attackers to restart rpd with a BGP update. Rpd accepts a tunnel encapsulation attribute containing a specifically malformed TLV without rejecting its invalid syntax, then crashes while processing it. An established BGP session is required, and each crafted update interrupts routing by crashing and restarting the routing protocol daemon.

CVSS severity8.7
High
EPSS probability0.57%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Input-validation failure in Juniper Networks Junos OS and Junos OS Evolved allows remote attackers to restart rpd with a BGP update. Rpd accepts a tunnel encapsulation attribute containing a specifically malformed TLV without rejecting its invalid syntax, then crashes while processing it. An established BGP session is required, and each crafted update interrupts routing by crashing and restarting the routing protocol daemon.

The record

CVE
CVE-2024-21598
Published
Apr 12, 2024
Updated
Aug 1, 2024
Vendor
Juniper Networks
Product
Junos OS Evolved
Classifications
CWE-1286, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 12, 2024CVE publishedPublication date reported by the CVE source.
  2. Aug 1, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=20.4 <20.4r3-s9
  2. Affected versionversion=20.4-EVO <20.4R3-S9-EVO
  3. Affected versionversion=21.2 <21.2r3-s7
  4. Affected versionversion=21.2-EVO <21.2R3-S7-EVO
  5. Affected versionversion=21.3 <21.3r3-s5
  6. Affected versionversion=21.3-EVO <21.3R3-S5-EVO
  7. Affected versionversion=21.4 <21.4r3-s4
  8. Affected versionversion=21.4-EVO <21.4R3-S5-EVO
  9. Affected versionversion=22.1 <22.1r3-s4
  10. Affected versionversion=22.1-EVO <22.1R3-S4-EVO
  11. Affected versionversion=22.2 <22.2r3-s3
  12. Affected versionversion=22.2-EVO <22.2R3-S3-EVO
  13. Affected versionversion=22.3-EVO <22.3R3-S1-EVO
  14. Affected versionversion=22.4-EVO <22.4R3-EVO
  15. Affected versionversion=23.2-EVO <23.2R1-S2-EVO, 23.2R2-EVO

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Juniper Networks · Junos OS Evolvedversion=20.4 <20.4r3-s9; version=20.4-EVO <20.4R3-S9-EVO; version=21.2 <21.2r3-s7; version=21.2-EVO <21.2R3-S7-EVO; version=21.3 <21.3r3-s5; version=21.3-EVO <21.3R3-S5-EVO; version=21.4 <21.4r3-s4; version=21.4-EVO <21.4R3-S5-EVO; version=22.1 <22.1r3-s4; version=22.1-EVO <22.1R3-S4-EVO; version=22.2 <22.2r3-s3; version=22.2-EVO <22.2R3-S3-EVO; version=22.3-EVO <22.3R3-S1-EVO; version=22.4-EVO <22.4R3-EVO; version=23.2-EVO <23.2R1-S2-EVO, 23.2R2-EVO
Juniper Networks · Junos OSversion=20.4 <20.4r3-s9; version=20.4 <20.4R3-S9; version=21.2 <21.2r3-s7; version=21.2 <21.2R3-S7; version=21.3 <21.3r3-s5; version=21.3 <21.3R3-S5; version=21.4 <21.4r3-s5; version=21.4 <21.4R3-S5; version=22.1 <22.1r3-s4; version=22.1 <22.1R3-S4; version=22.2 <22.2r3-s3; version=22.2 <22.2R3-S3; version=22.3 <22.3r3-s1; version=22.3 <22.3R3-S1; version=22.4 <22.4r3; version=22.4 <22.4R3; version=23.2 <23.2r1-s2; version=23.2 <23.2R1-S2, 23.2R2

Published CVSS scores

7.5Juniper Networks, Inc.CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
8.7Juniper Networks, Inc.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

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-1286Improper Validation of Syntactic Correctness of Input
T1499.004Endpoint Denial of Service: Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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