CVE-2026-33773
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
- Published
- Updated
- Reserved
- Assigned by
- juniper
Description
An Incorrect Initialization of Resource vulnerability in the packet forwarding engine (pfe) of Juniper Networks Junos OS on specific EX Series and QFX Series device allows an unauthenticated, network-based attacker to cause an integrity impact to downstream networks. When the same family inet or inet6 filter is applied on an IRB interface and on a physical interface as egress filter on EX4100, EX4400, EX4650 and QFX5120 devices, only one of the two filters will be applied, which can lead to traffic being sent out one of these interfaces which should have been blocked. This issue affects Junos OS on EX Series and QFX Series: * 23.4 version 23.4R2-S6, * 24.2 version 24.2R2-S3. No other Junos OS versions are affected.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| juniperCNA (assigner) | 4.0 | Medium6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/AU:Y/R:U/RE:M |
| juniperCNA (assigner) | 3.1 | Medium5.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:L/A:N |
| NVDNVD · Analyzed | 4.0 | Medium6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:N/SC:N/SI:L/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:Y/R:U/V:X/RE:M/U:X |
- EPSS (exploitation in 30 days)
- 0.20% · top 90% 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 6.9.
Weakness
Affected products
- affected 23.4R2-S6 – < 23.4R2-S7
- affected 24.2R2-S3 – < 24.2R2-S4
What to do
Solution: The following software releases have been updated to resolve this specific issue: 23.4R2-S7, 24.2R2-S4.
Workaround: Two different workarounds are available: 1. create the same filter but under a different name and apply that to one of the interfaces, so that each interface has a unique copy of the filter in question as shown in the following example: user@host# copy ... <filter> to ... <filter2> user@host# set interfaces irb unit <unit2> family inet/inet6 filter output <filter2> 2. configure the filter as "interface specific" by adding the keyword to the filter definition: [ firewall family inet/inet6 filter <filter> interface-specific ] which implicitly creates a copy of the original filter per applied interface.
Exploitation: Juniper SIRT is not aware of any malicious exploitation of this vulnerability.
References (1)
- https://kb.juniper.net/JSA107815 (opens in a new tab)vendor-advisory
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-2026-33773)Record last updated .