CVE-2023-44186

Junos OS and Junos OS Evolved: RPD crash when attempting to send a very long AS PATH to a non-4-byte-AS capable BGP neighbor

HIGH

7.5

CVSS Score

Published: October 11, 2023 at 08:08 PM UTC

Updated: June 17, 2026 at 06:27 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 Handling of Exceptional Conditions vulnerability in AS PATH processing of Juniper Networks Junos OS and Junos OS Evolved allows an attacker to send a BGP update message with an AS PATH containing a large number of 4-byte ASes, leading to a Denial of Service (DoS). Continued receipt and processing of these BGP updates will create a sustained Denial of Service (DoS) condition. This issue is hit when the router has Non-Stop Routing (NSR) enabled, has a non-4-byte-AS capable BGP neighbor, receives a BGP update message with a prefix that includes a long AS PATH containing large number of 4-byte ASes, and has to advertise the prefix towards the non-4-byte-AS capable BGP neighbor. Note: NSR is not supported on the SRX Series and is therefore not affected by this vulnerability. This issue affects: Juniper Networks Junos OS: * All versions prior to 20.4R3-S8; * 21.1 versions 21.1R1 and later; * 21.2 versions prior to 21.2R3-S6; * 21.3 versions prior to 21.3R3-S5; * 21.4 versions prior to 21.4R3-S5; * 22.1 versions prior to 22.1R3-S4; * 22.2 versions prior to 22.2R3-S2; * 22.3 versions prior to 22.3R2-S2, 22.3R3-S1; * 22.4 versions prior to 22.4R2-S1, 22.4R3. Juniper Networks Junos OS Evolved * All versions prior to 20.4R3-S8-EVO; * 21.1 versions 21.1R1-EVO and later; * 21.2 versions prior to 21.2R3-S6-EVO; * 21.3 versions prior to 21.3R3-S5-EVO; * 21.4 versions prior to 21.4R3-S5-EVO; * 22.1 versions prior to 22.1R3-S4-EVO; * 22.2 versions prior to 22.2R3-S2-EVO; * 22.3 versions prior to 22.3R2-S2-EVO, 22.3R3-S1-EVO; * 22.4 versions prior to 22.4R2-S1-EVO, 22.4R3-EVO.

Affected

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

Junos OS Evolved · Juniper

95%

Affected range stops below 20.4, so it looks safe — our inference, not a vendor statement

Junos · Juniper Networks

95%

v < 20.4v < 20.4R3-S821.1R1 ≤ v < 21.1*21.2 ≤ v < 21.2R3-S621.3 ≤ v < 21.3R3-S521.4 ≤ v < 21.4R3-S522.1 ≤ v < 22.1R3-S422.2 ≤ v < 22.2R3-S222.3 ≤ v < 22.3R2-S2, 22.3R3-S122.4 ≤ v < 22.4R2-S1, 22.4R320.4 20.4 r1 20.4 r1-s1 20.4 r2 20.4 r2-s1 20.4 r2-s2 20.4 r3 20.4 r3-s1 20.4 r3-s2 20.4 r3-s3 20.4 r3-s4 20.4 r3-s5 20.4 r3-s6 20.4 r3-s7 21.1 r1 21.1 r1-s1 21.1 r2 21.1 r2-s1 21.1 r2-s2 21.1 r3 21.1 r3-s1 21.1 r3-s2 21.1 r3-s3 21.1 r3-s4 21.1 r3-s5 21.1R1 21.2 21.2 r1 21.2 r1-s1 21.2 r1-s2 21.2 r2 21.2 r2-s1 21.2 r2-s2 21.2 r3 21.2 r3-s1 21.2 r3-s2 21.2 r3-s3 21.2 r3-s4 21.2 r3-s5 21.3 21.3 r1 21.3 r1-s1 21.3 r1-s2 21.3 r2 21.3 r2-s1 21.3 r2-s2 21.3 r3 21.3 r3-s1 21.3 r3-s2 21.3 r3-s3 21.3 r3-s4 21.4 21.4 r1 21.4 r1-s1 21.4 r1-s2 21.4 r2 21.4 r2-s1 21.4 r2-s2 21.4 r3 21.4 r3-s1 21.4 r3-s2 21.4 r3-s3 21.4 r3-s4 22.1 22.1 r1 22.1 r1-s1 22.1 r1-s2 22.1 r2 22.1 r2-s1 22.1 r2-s2 22.1 r3 22.1 r3-s1 22.1 r3-s2 22.1 r3-s3 22.2 22.2 r1 22.2 r1-s1 22.2 r1-s2 22.2 r2 22.2 r2-s1 22.2 r2-s2 22.2 r3 22.2 r3-s1 22.3 22.3 r1 22.3 r1-s1 22.3 r1-s2 22.3 r2 22.3 r2-s1 22.3 r3 22.4 22.4 r1 22.4 r1-s1 22.4 r1-s2 22.4 r2 23.1 r1 23.2 r1 23.2 r1-s1

Affected range stops below 20.4, so it looks safe — our inference, not a vendor statement

Affected range stops below 20.4R3-S8, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.1*, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.2R3-S6, 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-S2, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.3R2-S2, 22.3R3-S1, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.4R2-S1, 22.4R3, so it looks safe — our inference, not a vendor statement

Junos OS Evolved · Juniper Networks

60%

v < 20.4R3-S8-EVO21.1 ≤ v < 21.1*-EVO21.2 ≤ v < 21.2R3-S6-EVO21.3 ≤ v < 21.3R3-S5-EVO21.4 ≤ v < 21.4R3-S5-EVO22.1 ≤ v < 22.1R3-S4-EVO22.2 ≤ v < 22.2R3-S2-EVO22.3 ≤ v < 22.3R2-S2-EVO, 22.3R3-S1-EVO22.4 ≤ v < 22.4R2-S1-EVO, 22.4R3-EVO21.1 21.2 21.3 21.4 22.1 22.2 22.3 22.4

Affected range stops below 20.4R3-S8-EVO, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.1*-EVO, so it looks safe — our inference, not a vendor statement

Affected range stops below 21.2R3-S6-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-S2-EVO, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.3R2-S2-EVO, 22.3R3-S1-EVO, so it looks safe — our inference, not a vendor statement

Affected range stops below 22.4R2-S1-EVO, 22.4R3-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

https://supportportal.juniper.net/JSA73150

References (1)

Vendor AdvisoryMitigation

Source: [email protected]

https://supportportal.juniper.net/JSA73150

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

StatusMODIFIED

CWE

CWE-755

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