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Author Topic: DIR-850L - Security Firmware Patch - DNSmasq vulnerability (Nov.16)  (Read 19606 times)


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Firmware v1.21B06 (RevA) and v2.22B02 (revB) have been released. Links at the bottom. Note this is not a KRACK fix.

Before updating this firmware, the previous patch must have been updated on your router or this one will not work.

Please go here first and complete before updating the new patch. --> http://forums.dlink.com/index.php?topic=72539.0

Rev A - The 1.21B06 package will include 1.15 and 1.20 in the ZIP file. Read the update instructions to help you update to 1.21B06.

Seven flaws have been patched. The seven flaws include three that can be exploited to perform remote code execution, three more that can be used in denial of service attacks, and one information-leaking blunder. The full list of flaws is as follows:

CVE-2017-14491 Remote code execution in the DNS subsystem that can be exploited from the other side of the internet against public-facing systems and against stuff on the local network. The previously latest version had a two-byte overflow bug, which could be leveraged, and all prior builds had an unlimited overflow.

CVE-2017-14492 The second remote code execution flaw works via a heap-based overflow.

CVE-2017-14493 Google labels this one as trivial to exploit. It's a stack-based buffer overflow vulnerability that enables remote code execution if it's used in conjunction with the flaw below.

CVE-2017-14494 This is an information leak in DHCP which, when using in conjunction with CVE-2017-14493, lets an attacker bypass the security mechanism ASLR and attempt to run code on a target system.

CVE-2017-14495 A limited flaw this one, but can be exploited to launch a denial of service attack by exhausting memory. Dnsmasq is only vulnerable, however, if the command line switches --add-mac, --add-cpe-id or --add-subnet are used.

CVE-2017-14496 Here the DNS code performs invalid boundary checks, allowing a system to be crashed using an integer underflow leading to a huge memcpy() call. Android systems are affected if the attacker is local or tethered directly to the device.

CVE-2017-13704 A large DNS query can crash the software.



« Last Edit: April 13, 2018, 09:32:16 AM by GreenBay42 »


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Re: DIR-850L - Security Firmware Patch - DNSmasq vulnerability (Nov.16)
« Reply #1 on: August 31, 2018, 06:15:55 AM »

Can this patch described in your post be used with the DIR-822 router?


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Re: DIR-850L - Security Firmware Patch - DNSmasq vulnerability (Nov.16)
« Reply #2 on: August 31, 2018, 06:44:48 AM »

No it can not.
The 822 FW is still being worked on:

Can this patch described in your post be used with the DIR-822 router?
Cable: 1Gb/50Mb>NetGear CM1200>DIR-882>HP 24pt Gb Switch. COVR-1202/2202/3902,DIR-2660/80,3xDGL-4500s,DIR-LX1870,857,835,827,815,890L,880L,868L,836L,810L,685,657,3x655s,645,628,601,DNR-202L,DNS-345,DCS-933L,936L,960L and 8000LH.