Vulnerability · CVE-2024-21594
A Heap-based Buffer Overflow vulnerability in the Network Services Daemon (NSD) of Juniper Networks Junos OS allows authenticated, low privileged, local attacker to ca…
Published Jan 12, 2024 · catalog updated Jun 17, 2026 · the affected product
Last checked Nov 7, 2026. A connected source was read within the last 7 days.
Check if you run it
No confirmed exploitation is on record for CVE-2024-21594. EPSS is 0.17%. Act only if a listed version of the affected product is installed.
Gaps on this record
- No plain product name is stored. The page cannot tell you which product to check.
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
Same product and reporting
- CVE-2026-57054 · Medium
- CVE-2026-57032 · High
- CVE-2026-57031 · Medium
- CVE-2026-57030 · High
- CVE-2026-57027 · High
- Severity
- Medium5.5
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.17%
- Remediation
- Version ranges on file
- Affected products
- cpe juniper/junos
A Heap-based Buffer Overflow vulnerability in the Network Services Daemon (NSD) of Juniper Networks Junos OS allows authenticated, low privileged, local attacker to cause a Denial of Service (DoS). On an SRX 5000 Series device, when executing a specific command repeatedly, memory is corrupted, which leads to a Flow Processing Daemon (flowd) crash. The NSD process has to be restarted to restore services. If this issue occurs, it can be checked with the following command: user@host> request security policies check The following log message can also be observed: Error: policies are out of sync for PFE node .fpc .pic . This issue affects: Juniper Networks Junos OS on SRX 5000 Series * All versions earlier than 20.4R3-S6; * 21.1 versions earlier than 21.1R3-S5; * 21.2 versions earlier than 21.2R3-S4; * 21.3 versions earlier than 21.3R3-S3; * 21.4 versions earlier than 21.4R3-S3; * 22.1 versions earlier than 22.1R3-S1; * 22.2 versions earlier than 22.2R3; * 22.3 versions earlier than 22.3R2.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- cpe juniper/junos20.4
- cpe juniper/junos< 20.4
How to fix CVE-2024-21594
Upgrade
CVE-2024-21594 lists a fix boundary at 20.4. Compare the installed build with that boundary before you change production.
Version check
Affected < 20.4
Advisory
Open the cve_org record and follow its fix.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2024-21594. EPSS is 0.17%. Act only if a listed version of the affected product is installed.
Which versions are affected?
Compare what you have installed with 20.4, < 20.4. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
CWE-122: Heap-based Buffer Overflow; CWE-787: Out-of-bounds Write. EPSS 0.17%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Technology hubs
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
Jan 12, 2024 · Monitored products — high
Detected
A Heap-based Buffer Overflow vulnerability in the Network Services Daemon (NSD) of Juniper Networks Junos OS allows authenticated, low privileged, local attacker to cause a Denial of Service (DoS). On an SRX 5000 Series device, when executing a specific command repeatedly, memory is corrupted, which leads to a Flow Processing Daemon (flowd) crash. The NSD process has to be restarted to restore ser
Jun 17, 2026 · Monitored products — high
Updated
A Heap-based Buffer Overflow vulnerability in the Network Services Daemon (NSD) of Juniper Networks Junos OS allows authenticated, low privileged, local attacker to cause a Denial of Service (DoS). On an SRX 5000 Series device, when executing a specific command repeatedly, memory is corrupted, which leads to a Flow Processing Daemon (flowd) crash. The NSD process has to be restarted to restore ser
Sources
- CVE.orgVulnerability recordCVE-2024-21594
Official CVE identifier
cve.org - Monitored products — highVendor advisoryCVE-2024-21594
A Heap-based Buffer Overflow vulnerability in the Network Services Daemon (NSD) of Juniper Networks Junos OS allows authenticated, low privileged, local attacker to cause a Denial of Service (DoS). On an SRX 5000 Series device, when executing a specific command repeatedly, memory is corrupted, which leads to a Flow Processing Daemon (flowd) crash. The NSD process has to be restarted to restore ser
nvd.nist.gov
References
Freshness
Last verified in this catalog Nov 7, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.
- CVE.orgNov 7, 2026
- Monitored products — highNov 7, 2026