CVE-2026-57029
A Missing Synchronization vulnerability in the flow collector handler of Juniper Networks Junos OS Evolved on QFX Series allows an adjacent, unauthenticated attacker to cause a Denial-of-Service (DoS).
Does this matter?
Lower severity and a low EPSS score (0.19%). Track it; it rarely justifies an emergency change on its own.
Description
A Missing Synchronization vulnerability in the flow collector handler of Juniper Networks Junos OS Evolved on QFX Series allows an adjacent, unauthenticated attacker to cause a Denial-of-Service (DoS). When the reachability of an sFlow collector changes, the corresponding next-hop entry is updated. If this update occurs simultaneously with the sFlow thread accessing the next-hop data (which is outside the attackers control), it causes the evo-pfemand process to crash, impacting all traffic forwarding until the automatic process restart has completed. This issue affects Junos OS Evolved on QFX Series: * all 23.2 versions, * 23.4 versions before 23.4R2-S7-EVO, * 24.2 versions before 24.2R2-S5-EVO, * 24.4 versions before 24.4R2-S3-EVO, * 25.2 versions before 25.2R2-EVO.
- CVSS 4.0
- 6.0 MEDIUMCVSS:4.0/AV:A/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/M
- EPSS
- 0.19% probability · 9th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-820
- Affected
- juniper/junos os evolved
- Source
- sirt@juniper.net
EPSS 0.2% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://supportportal.juniper.net/JSA110089Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.