CVE-2024-39526

HIGHCVSS 7.1/10EPSS 0.35%

Last modified

CVE-2024-39526 is a high-severity vulnerability rated 7.1/10 on the CVSS scale. An Improper Handling of Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS on MX Series with MPC10/MPC11/LC9600 line cards, EX9200 with EX9200-15C lines cards, MX304 devices, and Juniper Networks Junos OS Evolved on PTX Series, allows an attacker sending malformed DHCP packets to cause ingress packet processing to stop, leading to a Denial of Service (DoS).  Continued receipt and processing of these packets will create a sustained Denial of Service (DoS) condition. This issue only occurs if DHCP snooping is enabled. See configuration below. This issue can be detected using following commands. EPSS estimates a 0.35% chance of exploitation in the next 30 days.

Description

An Improper Handling of Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS on MX Series with MPC10/MPC11/LC9600 line cards, EX9200 with EX9200-15C lines cards, MX304 devices, and Juniper Networks Junos OS Evolved on PTX Series, allows an attacker sending malformed DHCP packets to cause ingress packet processing to stop, leading to a Denial of Service (DoS).  Continued receipt and processing of these packets will create a sustained Denial of Service (DoS) condition. This issue only occurs if DHCP snooping is enabled. See configuration below. This issue can be detected using following commands. Their output will display the interface status going down: user@device>show interfaces <if--x/x/x> user@device>show log messages | match <if--x/x/x> user@device>show log messages ==> will display the "[Error] Wedge-Detect : Host Loopback Wedge Detected: PFE: no," logs. This issue affects: Junos OS on MX Series with MPC10/MPC11/LC9600 line cards, EX9200 with EX9200-15C line cards, and MX304: * All versions before 21.2R3-S7, * from 21.4 before 21.4R3-S6, * from 22.2 before 22.2R3-S3, * all versions of 22.3, * from 22.4 before 22.4R3, * from 23.2 before 23.2R2; Junos OS Evolved on PTX Series: * from 19.3R1-EVO before 21.2R3-S8-EVO, * from 21.4-EVO before 21.4R3-S7-EVO, * from 22.1-EVO before 22.1R3-S6-EVO, * from 22.2-EVO before 22.2R3-S5-EVO, * from 22.3-EVO before 22.3R3-S3-EVO, * from 22.4-EVO before 22.4R3-S1-EVO, * from 23.2-EVO before 23.2R2-S2-EVO, * from 23.4-EVO before 23.4R2-EVO. Junos OS Evolved releases prior to 19.3R1-EVO are unaffected by this vulnerability

Metrics

CVSS 3.1
6.5/10

CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CVSS 4.0
7.1/10

CVSS:4.0/AV:A/AC:L/AT:N/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:U/V:X/RE:X/U:X

EPSS Probability
0.35%

27.1th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

VendorProductVersionsUpdate
JuniperJunos Os Evolved>= 19.4, < 21.2
JuniperJunos Os Evolved19.3R1
JuniperJunos Os Evolved21.2
JuniperJunos Os Evolved21.4
JuniperJunos Os Evolved22.1
JuniperJunos Os Evolved22.2
JuniperJunos Os Evolved22.3
JuniperJunos Os Evolved22.4
JuniperJunos Os Evolved23.2
JuniperJunos Os Evolved23.4
JuniperJunos< 21.2
JuniperJunos21.2
JuniperJunos21.4
JuniperJunos22.2
JuniperJunos22.3
JuniperJunos22.4
JuniperJunos23.2

References

Timeline

Published
Last Modified
Status
Analyzed

Frequently Asked Questions

What is CVE-2024-39526?
An Improper Handling of Exceptional Conditions vulnerability in packet processing of Juniper Networks Junos OS on MX Series with MPC10/MPC11/LC9600 line cards, EX9200 with EX9200-15C lines cards, MX304 devices, and Juniper Networks Junos OS Evolved on PTX Series, allows an attacker sending malformed DHCP packets to cause ingress packet processing to stop, leading to a Denial of Service (DoS).  Continued receipt and processing of these packets will create a sustained Denial of Service (DoS) condition. This issue only occurs if DHCP snooping is enabled. See configuration below. This issue can be detected using following commands. Their output will display the interface status going down: user@device>show interfaces <if--x/x/x> user@device>show log messages | match <if--x/x/x> user@device>show log messages ==> will display the "[Error] Wedge-Detect : Host Loopback Wedge Detected: PFE: no," logs. This issue affects: Junos OS on MX Series with MPC10/MPC11/LC9600 line cards, EX9200 with EX9200-15C line cards, and MX304: * All versions before 21.2R3-S7, * from 21.4 before 21.4R3-S6, * from 22.2 before 22.2R3-S3, * all versions of 22.3, * from 22.4 before 22.4R3, * from 23.2 before 23.2R2; Junos OS Evolved on PTX Series: * from 19.3R1-EVO before 21.2R3-S8-EVO, * from 21.4-EVO before 21.4R3-S7-EVO, * from 22.1-EVO before 22.1R3-S6-EVO, * from 22.2-EVO before 22.2R3-S5-EVO, * from 22.3-EVO before 22.3R3-S3-EVO, * from 22.4-EVO before 22.4R3-S1-EVO, * from 23.2-EVO before 23.2R2-S2-EVO, * from 23.4-EVO before 23.4R2-EVO. Junos OS Evolved releases prior to 19.3R1-EVO are unaffected by this vulnerability
How severe is CVE-2024-39526?
CVE-2024-39526 has a CVSS score of 7.1/10 (HIGH severity). The EPSS model estimates a 0.35% probability of exploitation in the next 30 days.
How do I fix CVE-2024-39526?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2024-39526?

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Source: NVD / NIST