VDB
CVE-2026-33781
CVE-2026-33781
PUBLISHED
CVSS 6.5 MEDIUM
An Improper Check for Unusual or Exceptional Conditions vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX and QFX Series devices allow an unauthenticated, adjacent attacker to cause a complete Denial of Service (DoS). On EX4k, and QFX5k platforms configured as service-provider edge devices, if L2PT is enabled on the UNI and VSTP is enabled on NNI in VXLAN scenarios, receiving VSTP BPDUs on UNI leads to packet buffer allocation failures, resulting in the device to not pass traffic anymore until it is manually recovered with a restart.This issue affects Junos OS: * 24.4 releases before 24.4R2, * 25.2 releases before 25.2R1-S1, 25.2R2. This issue does not affect Junos OS releases before 24.4R1.
EPSS 0.02% · 6.2th percentile
Risk Scores
CVSS 3.1
6.5
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score
0.02%
6.2th percentile
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Juniper Networks | Junos OS | 24.4, 25.2, 0 |
Timeline
- Apr 9, 2026 CVE Published
- May 18, 2026 EPSS Score
- May 19, 2026 EPSS Score
- May 20, 2026 EPSS Score
- May 21, 2026 EPSS Score
- May 22, 2026 EPSS Score
- May 23, 2026 EPSS Score
- May 24, 2026 EPSS Score
- May 25, 2026 EPSS Score
- May 26, 2026 EPSS Score
- May 27, 2026 EPSS Score
- May 28, 2026 EPSS Score
References
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-SRX-Series-MX-Series-When-a-specifically-malformed-first-ISAKMP-packet-is-received-kmd-iked-crashes-CVE-2026-33778 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-CTP-OS-Configuring-password-requirements-does-not-work-which-permits-the-use-of-weak-passwords-CVE-2026-33771 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-Privileged-local-user-can-gain-access-to-a-Linux-based-FPC-as-root-CVE-2025-30650 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-SRX-Series-Insufficient-certificate-verification-for-device-to-SD-cloud-communication-CVE-2026-33779 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-and-Junos-OS-Evolved-CVE-2022-24805-resolved-in-net-SNMP advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-MX-Series-Missing-Authorization-for-specific-request-CLI-commands-in-a-JDM-CSDS-scenario-CVE-2026-33785 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-EX-Series-QFX-Series-In-a-VXLAN-scenario-when-specific-control-protocol-packets-are-received-memory-leaks-and-eventually-no-traffic-is-passed-CVE-2026-33781 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-MX-Series-Mismatch-between-configured-and-received-packet-types-causes-memory-leak-in-bbe-smgd-CVE-2026-33775 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-MX-Series-Firewall-filters-on-lo0-non-0-in-the-default-routing-instance-are-not-in-effect-CVE-2026-33774 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-SRX1600-SRX2300-SRX4300-When-a-specific-show-command-is-executed-chassisd-crashes-CVE-2026-33786 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-vLWC-Default-password-is-not-required-to-be-changed-which-allows-unauthorized-high-privileged-access-CVE-2026-33784 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-MX-Series-In-specific-DHCPv6-scenarios-jdhcpd-memory-increases-continuously-with-subscriber-logouts-CVE-2026-33782 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-EX-Series-QFX-Series-If-the-same-egress-filter-is-configured-on-both-an-IRB-and-a-physical-interface-one-of-those-is-not-applied-CVE-2026-33773 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-and-Junos-OS-Evolved-A-high-frequency-of-connecting-and-disconnecting-netconf-sessions-causes-management-unavailability-CVE-2026-21919 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-and-Junos-OS-Evolved-An-attacker-sending-a-specific-genuine-BGP-packet-causes-a-BGP-reset-CVE-2026-33797 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-and-Junos-OS-Evolved-Specific-low-privileged-CLI-command-exposes-sensitive-information-CVE-2026-33776 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-SRX1500-SRX4100-SRX4200-SRX4600-When-a-specific-show-command-is-executed-chassisd-crashes-CVE-2026-33787 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-SRX-Series-In-a-NAT64-configuration-receipt-of-a-specific-malformed-ICMPv6-packet-will-cause-the-srxpfe-process-to-crash-and-restart-CVE-2026-33790 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-and-Junos-OS-Evolved-Execution-of-crafted-CLI-commands-allows-for-arbitrary-shell-injection-as-root-CVE-2026-33791 advisory
- https://supportportal.juniper.net/s/article/2026-04-Security-Bulletin-Junos-OS-A-low-privileged-user-can-escalate-their-privileges-so-that-they-can-login-as-root-CVE-2026-21916 advisory
…and 6 more