CVE-2024-39559
Junos OS Evolved: Receipt of a specific TCP packet may result in a system crash (vmcore) on dual RE systems with NSR enabled
An Improper Check for Unusual or Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS Evolved may allow a network-based unauthenticated attacker to crash the device (vmcore) by sending a specific TCP packet over an established TCP session with MD5 authentication enabled, destined to an accessible port on the device, resulting in a Denial of Service (DoS). The receipt of this packet must occur within a specific timing window outside the attacker's control (i.e., race condition).
Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition.
This issue only affects dual RE systems with Nonstop Active Routing (NSR) enabled. Exploitation can only occur over TCP sessions with MD5 authentication enabled (e.g., BGP with MD5 authentication).
This issue affects Junos OS Evolved:
- All versions before 21.2R3-S8-EVO,
- from 21.4-EVO before 21.4R3-S6-EVO,
- from 22.1-EVO before 22.1R3-S4-EVO,
- from 22.2-EVO before 22.2R3-S4-EVO,
- from 22.3-EVO before 22.3R3-S3-EVO,
- from 22.4-EVO before 22.4R2-S2-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 Evolved: Receipt of a specific TCP packet may result in a system crash (vmcore) on dual RE systems with NSR enabled
An Improper Check for Unusual or Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS Evolved may allow a network-based unauthenticated attacker to crash the device (vmcore) by sending a specific TCP packet over an established TCP session with MD5 authentication enabled, destined to an accessible port on the device, resulting in a Denial of Service (DoS). The receipt of this packet must occur within a specific timing window outside the attacker's control (i.e., race condition).
Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition.
This issue only affects dual RE systems with Nonstop Active Routing (NSR) enabled. Exploitation can only occur over TCP sessions with MD5 authentication enabled (e.g., BGP with MD5 authentication).
This issue affects Junos OS Evolved:
- All versions before 21.2R3-S8-EVO,
- from 21.4-EVO before 21.4R3-S6-EVO,
- from 22.1-EVO before 22.1R3-S4-EVO,
- from 22.2-EVO before 22.2R3-S4-EVO,
- from 22.3-EVO before 22.3R3-S3-EVO,
- from 22.4-EVO before 22.4R2-S2-EVO, 22.4R3-EVO.
- Record
CVE-2024-39559- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/R:A - CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-754
- Updated
- 2026-11-02
EUVDEUVD-2024-38085
An Improper Check for Unusual or Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS Evolved may allow a network-based unauthenticated attacker to crash the device (vmcore) by sending a specific TCP packet over an established TCP session with MD5 authentication enabled, destined to an accessible port on the device, resulting in a Denial of Service (DoS). The receipt of this packet must occur within a specific timing window outside the attacker's control (i.e., race condition).
Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition.
This issue only affects dual RE systems with Nonstop Active Routing (NSR) enabled. Exploitation can only occur over TCP sessions with MD5 authentication enabled (e.g., BGP with MD5 authentication).
This issue affects Junos OS Evolved:
- All versions before 21.2R3-S8-EVO,
- from 21.4-EVO before 21.4R3-S6-EVO,
- from 22.1-EVO before 22.1R3-S4-EVO,
- from 22.2-EVO before 22.2R3-S4-EVO,
- from 22.3-EVO before 22.3R3-S3-EVO,
- from 22.4-EVO before 22.4R2-S2-EVO, 22.4R3-EVO.
- Record
EUVD-2024-38085- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/R:A - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-473h-3vgg-7379
An Improper Check for Unusual or Exceptional Conditions vulnerability in packet processing of...
An Improper Check for Unusual or Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS Evolved may allow a network-based unauthenticated attacker to crash the device (vmcore) by sending a specific TCP packet over an established TCP session with MD5 authentication enabled, destined to an accessible port on the device, resulting in a Denial of Service (DoS). The receipt of this packet must occur within a specific timing window outside the attacker's control (i.e., race condition).
Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition.
This issue only affects dual RE systems with Nonstop Active Routing (NSR) enabled. Exploitation can only occur over TCP sessions with MD5 authentication enabled (e.g., BGP with MD5 authentication).
This issue affects Junos OS Evolved:
- All versions before 21.2R3-S8-EVO,
- from 21.4-EVO before 21.4R3-S6-EVO,
- from 22.1-EVO before 22.1R3-S4-EVO,
- from 22.2-EVO before 22.2R3-S4-EVO,
- from 22.3-EVO before 22.3R3-S3-EVO,
- from 22.4-EVO before 22.4R2-S2-EVO, 22.4R3-EVO.
- Record
GHSA-473h-3vgg-7379- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:A/V:X/RE:X/U:X - CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-754
- Updated
- 2026-11-02
NVD
An Improper Check for Unusual or Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS Evolved may allow a network-based unauthenticated attacker to crash the device (vmcore) by sending a specific TCP packet over an established TCP session with MD5 authentication enabled, destined to an accessible port on the device, resulting in a Denial of Service (DoS). The receipt of this packet must occur within a specific timing window outside the attacker's control (i.e., race condition).
Continued receipt and processing of this packet will create a sustained Denial of Service (DoS) condition.
This issue only affects dual RE systems with Nonstop Active Routing (NSR) enabled. Exploitation can only occur over TCP sessions with MD5 authentication enabled (e.g., BGP with MD5 authentication).
This issue affects Junos OS Evolved:
- All versions before 21.2R3-S8-EVO,
- from 21.4-EVO before 21.4R3-S6-EVO,
- from 22.1-EVO before 22.1R3-S4-EVO,
- from 22.2-EVO before 22.2R3-S4-EVO,
- from 22.3-EVO before 22.3R3-S3-EVO,
- from 22.4-EVO before 22.4R2-S2-EVO, 22.4R3-EVO.
- Record
CVE-2024-39559- CVSS 4.0
- 8.2 High
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:A/V:X/RE:X/U:X - CVSS 3.1
- 5.9 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-754
- 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-2024-39559 is a high vulnerability (CVSS 8.2) in Juniper Junos Os Evolved, published July 10, 2024. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.40%, the 34th percentile. No source names a fixed version.