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
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
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
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.
- Record
CVE-2023-44186- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-755
- Updated
- 2026-11-02
EUVDEUVD-2023-48545
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.
- Record
EUVD-2023-48545- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-8pvv-px4f-4px7
An Improper Handling of Exceptional Conditions vulnerability in AS PATH processing of Juniper...
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.
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;
- 23.2 versions prior to 23.2R2.
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;
- 23.2 versions prior to 23.2R2-EVO.
- Record
GHSA-8pvv-px4f-4px7- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-755
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2023-44186- CVSS 3.1
- 7.5 High
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-755
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2023-44186 is a high vulnerability (CVSS 7.5) in Juniper Junos, published October 11, 2023. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.64%, the 51st percentile. No source names a fixed version.