CVE-2025-30649 Junos OS: MX240, MX480, MX960 with SPC3: An attacker sending specific packets will cause a CPU utilization DoS.
An unauthenticated attacker can cause a CPU denial of service on Juniper MX routers with SPC3 cards by sending specific spoofed packets.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2025-30649?
CVE-2025-30649 is a high-severity denial of service vulnerability in Juniper Junos, published on 9 Apr 2025. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
An Improper Input Validation vulnerability in the syslog stream TCP transport of Juniper Networks Junos OS on MX240, MX480 and MX960 devices with MX-SPC3 Security Services Card allows an unauthenticated, network-based attacker, to send specific spoofed packets to cause a CPU Denial of Service (DoS) to the MX-SPC3 SPUs.
Continued receipt and processing of these specific packets will sustain the DoS condition.
This issue affects Junos OS: * All versions before 22.2R3-S6, * from 22.4 before 22.4R3-S4, * from 23.2 before 23.2R2-S3, * from 23.4 before 23.4R2-S4, * from 24.2 before 24.2R1-S2, 24.2R2
An indicator of compromise will indicate the SPC3 SPUs utilization has spiked.
For example: user@device> show services service-sets summary Service sets CPU Interface configured Bytes used Session bytes used Policy bytes used utilization "interface" 1 "bytes" (percent%) "sessions" ("percent"%) "bytes" ("percent"%) 99.97 % OVLD <<<<<< look for high CPU usage
Weakness: CWE-20
Which versions are affected by CVE-2025-30649?
It affects 1 product.
Products include Juniper Junos.
How do I fix CVE-2025-30649?
No fix has been published for CVE-2025-30649 yet. Limit exposure of the affected software until one is available.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2025-30649 being exploited?
There is no known exploitation of CVE-2025-30649 in the wild and no public exploit code.
Other vulnerabilities in Juniper Junos
- CVE-2023-36845 Juniper Junos OS EX Series and SRX Series PHP External Variable Modification
- CVE-2020-1631 Juniper Junos OS Path Traversal
- CVE-2025-21590 Juniper Junos OS Improper Isolation or Compartmentalization
- CVE-2023-36851 Juniper Junos OS SRX Series Missing Authentication for Critical Function
- CVE-2023-36844 Juniper Junos OS EX Series PHP External Variable Modification
Sources
Also known as GHSA-8279-hg76-9fpw.