Juniper: >> Qfx5250 Security Vulnerabilities
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 Score
6.0
EPSS Score
0.002
Published
2026-07-09
A Return of Pointer Value Outside of Expected Range vulnerability in the fileio library of Juniper Networks Junos OS and Junos OS Evolved allows a local, low-privilged attacker to cause a Denial-of-Service (DoS).
On EX Series, QFX Series and MX Series a low-privileged attacker issuing a specific 'show l2-learning' command will cause an l2ald crash which will lead to a temporary service impact for all layer 2 services until the process has automatically restarted.
This issue affects EX Series, QFX Series, MX Series:
Junos OS:
* all versions before 23.2R2-S7,
* 23.4 versions before 23.4R2-S7,
* 24.2 versions before 24.2R2,
* 24.4 versions before 24.4R1-S2.
Junos OS Evolved:
* all versions before 23.2R2-S7-EVO,
* 23.4 versions before 23.4R2-S8-EVO,
* 24.2 versions before 24.2R2-EVO,
* 24.4 versions before 24.4R1-S3-EVO.
CVSS Score
6.8
EPSS Score
0.001
Published
2026-07-09