CVE-2022-22174: A vulnerability in the processing of inbound IPv6 packets in Juniper Networks Junos OS on QFX5000 Series and EX4600 switches may cause the memory to not be free

A vulnerability in the processing of inbound IPv6 packets in Juniper Networks Junos OS on QFX5000 Series and EX4600 switches may cause the memory to not be free

A vulnerability in the processing of inbound IPv6 packets in Juniper Networks Junos OS on QFX5000 Series and EX4600 switches may cause the memory to not be freed, leading to a packet DMA memory leak, and eventual Denial of Service (DoS) condition. Once the condition occurs, further packet processing will be impacted, creating a sustained Denial of Service (DoS) condition. The following error logs may be observed using the "show heap" command and the device may eventually run out of memory if such packets are received continuously. Jan 12 12:00:00 device-name fpc0 (buf alloc) failed allocating packet buffer Jan 12 12:00:01 device-name fpc0 (buf alloc) failed allocating packet buffer user@device-name> request pfe execute target fpc0 timeout 30 command "show heap" ID Base Total(b) Free(b) Used(b) % Name -- ---------- ----------- ----------- ----------- --- ----------- 0 246fc1a8 536870488 353653752 183216736 34 Kernel 1 91800000 16777216 12069680 4707536 28 DMA 2 92800000 75497472 69997640 5499832 7 PKT DMA DESC 3 106fc000 335544320 221425960 114118360 34 Bcm_sdk 4 97000000 176160768 200 176160568 99 Packet DMA <<<<<<<<<<<<<< 5 903fffe0 20971504 20971504 0 0 Blob This issue affects Ju

Description from the National Vulnerability Database, published by sirt@juniper.net

What it means for a small business

Junos OS is network equipment or remote-access software: the box between your office and the internet. These are a favorite target because breaking one opens the whole office.

If an IT provider set it up, ask them to confirm the firmware version and the date it was updated. If nobody looks after it, that's the bigger problem.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.93%, higher than 60% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 29, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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