CVE-2018-0049: A NULL Pointer Dereference vulnerability in Juniper Networks Junos OS allows an attacker to cause the Junos OS kernel to crash.

A NULL Pointer Dereference vulnerability in Juniper Networks Junos OS allows an attacker to cause the Junos OS kernel to crash.

A NULL Pointer Dereference vulnerability in Juniper Networks Junos OS allows an attacker to cause the Junos OS kernel to crash. Continued receipt of this specifically crafted malicious MPLS packet will cause a sustained Denial of Service condition. This issue require it to be received on an interface configured to receive this type of traffic. Affected releases are Juniper Networks Junos OS: 12.1X46 versions above and including 12.1X46-D76 prior to 12.1X46-D81 on SRX100, SRX110, SRX210, SRX220, SRX240m, SRX550m SRX650, SRX300, SRX320, SRX340, SRX345, SRX1500, SRX4100, SRX4200, SRX4600 and vSRX; 12.3R12-S10; 12.3X48 versions above and including 12.3X48-D66 prior to 12.3X48-D75 on SRX100, SRX110, SRX210, SRX220, SRX240m, SRX550m SRX650, SRX300, SRX320, SRX340, SRX345, SRX1500, SRX4100, SRX4200, SRX4600 and vSRX; 14.1X53-D47 on EX2200/VC, EX3200, EX3300/VC, EX4200, EX4300, EX4550/VC, EX4600, EX6200, EX8200/VC (XRE), QFX3500, QFX3600, QFX5100; 14.1X53 versions above and including 14.1X53-D115 prior to 14.1X53-D130 on QFabric System; 15.1 versions above and including 15.1F6-S10; 15.1R4-S9; 15.1R6-S6; 15.1 versions above and including 15.1R7 prior to 15.1R7-S2; 15.1X49 versions above and

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 2.2%, higher than 82% of CVEs. That’s above average: worth scheduling this week. Scored November 14, 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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