CVE-2024-21603
Junos OS: MX Series: Gathering statistics in a scaled SCU/DCU configuration will lead to a device crash
- Published
- Updated
- Reserved
- Assigned by
- juniper
Description
An Improper Check for Unusual or Exceptional Conditions vulnerability in the kernel of Juniper Network Junos OS on MX Series allows a network based attacker with low privileges to cause a denial of service. If a scaled configuration for Source class usage (SCU) / destination class usage (DCU) (more than 10 route classes) is present and the SCU/DCU statistics are gathered by executing specific SNMP requests or CLI commands, a 'vmcore' for the RE kernel will be seen which leads to a device restart. Continued exploitation of this issue will lead to a sustained DoS. This issue only affects MX Series devices with MPC10, MPC11 or LC9600, and MX304. No other MX Series devices are affected. This issue affects Juniper Networks Junos OS: * All versions earlier than 20.4R3-S9; * 21.2 versions earlier than 21.2R3-S6; * 21.3 versions earlier than 21.3R3-S5; * 21.4 versions earlier than 21.4R3; * 22.1 versions earlier than 22.1R3; * 22.2 versions earlier than 22.2R2; * 22.3 versions earlier than 22.3R2.
Timeline
ID reserved
By juniper
- 16 days later
· 16 days later
Published
- 17 months later
· 17 months later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| juniperCNA (assigner) | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | Medium6.5 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.51% · top 56% of all CVEs (7 Nov 2026)
- CISA SSVC
- Exploitation: none · Automatable: yes · Technical impact: partial
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 6.5.
Weakness
Affected products
- affected < 20.4R3-S9
- affected 21.2 – < 21.2R3-S6
- affected 21.3 – < 21.3R3-S5
- affected 21.4 – < 21.4R3
- affected 22.1 – < 22.1R3
- affected 22.2 – < 22.2R2
- affected 22.3 – < 22.3R2
What to do
Solution: The following software releases have been updated to resolve this specific issue: Junos OS 20.4R3-S9, 21.2R3-S6, 21.3R3-S5, 21.4R3, 22.1R3, 22.2R2, 22.3R2, 22.4R1, and all subsequent releases.
Workaround: There are no known workarounds for this issue.
Exploitation: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
References (2)
- https://supportportal.juniper.net/JSA75744 (opens in a new tab)vendor-advisoryx_transferred
- https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:L (opens in a new tab)technical-descriptionx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2024-21603)Record last updated .