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Infocon: green

14 min 33 sec ago
ISC Stormcast For Wednesday, May 24th 2017 https://isc.sans.edu/podcastdetail.html?id=5514
Categories: Security Posts

ISC Stormcast For Wednesday, May 24th 2017 https://isc.sans.edu/podcastdetail.html?id=5514, (Wed, May 24th)

9 hours 36 min ago
(c) SANS Internet Storm Center. https://isc.sans.edu Creative Commons Attribution-Noncommercial 3.0 United States License.
Categories: Security Posts

Jaff ransomware gets a makeover, (Wed, May 24th)

9 hours 56 min ago
Introduction Since 2017-05-11, a new ransomware named Jaff has been distributed through malicious spam (malspam) from the Necurs botnet. This malspam uses PDF attachments with embedded Word documents containing malicious macros. border-width:2px" />
Shown above: Flow chart for this infection chain. Prior to Jaff, weve seen waves of malspam using the same PDF attachment/embedded Word doc scheme to push Locky ransomware. Prior to that, this type of malspam was pushing Dridex. With all the recent news about WannaCry ransomware, people might forget Jaff is an ongoing threat. Worse yet, some people might not know about it at all since its debut about 2 weeks ago. Jaff has already gotten a makeover, so an infected host looks noticeably different now. With that in mind, todays diary reviews a wave of malspam pushing Jaff ransomware from Tuesday 2017-05-23. The emails This specific wave of malspam used a fake invoice theme. It started on Tuesday 2017-05-23 as early as 13:22 UTC and lasted until sometime after 20:00 UTC. I collected 20 emails for today border-width:2px" />
Shown above: border-width:2px" />
Shown above: border-width:2px" />
Shown above: Screenshot from one of the emails. As stated earlier, these emails all have PDF attachments, and each one contains an embedded Word document. border-width:2px" />
Shown above: border-width:2px" />
Shown above: The embedded Word document with malicious macros. The traffic Follow the entire infection chain, and youll see minimal network traffic compared to other types of malware. The Word macros generate an initial URL to download an encoded Jaff binary, then we see one other URL for post-infection callback from an infected host. The initial HTTP request for Jaff returns an encoded binary thats been XORed with the ASCII string I6cqcYo7wQ. Post-infection traffic merely returns the string Created border-width:2px" />
Shown above: border-width:2px" />
Shown above: border-width:2px" />
Shown above: border-width:2px" />
Shown above: Alerts on the traffic using Security Onion with Suricata and the EmergingThreats Open ruleset. The infected Windows host The encoded binary from this wave of malspam was stored to the users AppData\Local\Temp directory as lodockap8. Then it was decoded and stored as levinsky8.exe in the same directory. border-width:2px" />
Shown above: The users AppData\Local\Temp directory from an infected host on 2017-05-23. On Tuesday 2017-05-23, Jaff ransomware had a makeover. border-width:2px" />
Shown above: border-width:2px" />
Shown above: Desktop of a Windows host infected with a Jaff ransomware sample from 2017-05-23. Encrypted files had been previously appended with the .jaff file extension. On Tuesday 2017-05-23, encrypted files from my infected host were appended with a .wlu file extension. border-width:2px" />
Shown above: Jaff decryptor from a Windows host infected on 2017-05-23. Indicators of Compromise (IoCs) The following are examples of email subject lines and attachment names from Tuesday 2017-05-23:
  • Subject: Invoice(00-5523) -- Attachment name: 68-5182.pdf
  • Subject: Invoice(00-5832) -- Attachment name: 72-6353.pdf
  • Subject: Invoice(08-4031) -- Attachment name: 28-3137.pdf
  • Subject: Invoice(09-5337) -- Attachment name: 98-9897.pdf
  • Subject: Invoice(19-9273) -- Attachment name: 68-6414.pdf
  • Subject: Invoice(23-0458) -- Attachment name: 53-3366.pdf
  • Subject: Invoice(27-7813) -- Attachment name: 95-1750.pdf
  • Subject: Invoice(28-3137) -- Attachment name: 68-4200.pdf
  • Subject: Invoice(53-3366) -- Attachment name: 61-7808.pdf
  • Subject: Invoice(54-9434) -- Attachment name: 78-8672.pdf
  • Subject: Invoice(61-7808) -- Attachment name: 00-5832.pdf
  • Subject: Invoice(68-4200) -- Attachment name: 98-3753.pdf
  • Subject: Invoice(68-5182) -- Attachment name: 54-9434.pdf
  • Subject: Invoice(68-6414) -- Attachment name: 27-7813.pdf
  • Subject: Invoice(72-6353) -- Attachment name: 08-4031.pdf
  • Subject: Invoice(78-8672) -- Attachment name: 23-0458.pdf
  • Subject: Invoice(88-6908) -- Attachment name: 19-9273.pdf
  • Subject: Invoice(95-1750) -- Attachment name: 00-5523.pdf
  • Subject: Invoice(98-3753) -- Attachment name: 88-6908.pdf
  • Subject: Invoice(98-9897) -- Attachment name: 09-5337.pdf
The following are examples of spoofed email senders from Tuesday 2017-05-23:
  • ALISA PICKARD ALISA.PICKARD@ADAMSINSTALLATIONS.CO.UK
  • ALYSSA BUTLING ALYSSA.BUTLING@MATTRICHLING.COM
  • CAROLYN BOSTON CAROLYN.BOSTON@FLORIN.FR
  • DENIS SENIOR DENIS.SENIOR@INFOTEC.NO
  • DUSTY HAMMOND DUSTY.HAMMOND@EASTWELLIRONWORKS.CO.UK
  • ELAINE BARKER ELAINE.BARKER@SCHIONNINGDEVELOPMENT.DK
  • FREDRIC RALLI FREDRIC.RALLI@RVAGROCERYSHOPPER.COM
  • GENA CLYDE GENA.CLYDE@CORTE.CH
  • HERMINIA UREN HERMINIA.UREN@BIGBOYPUZZLES.COM
  • JENNA LAMPET JENNA.LAMPET@ALIF-INTERNATIONAL.COM
  • LILLIE TRAVERS LILLIE.TRAVERS@CHANGEAGENTS.BIZ
  • LUPE FERN LUPE.FERN@DWTAXPREP.COM
  • MEAGAN FALKENBERG MEAGAN.FALKENBERG@MIKEPRICE.INFO
  • MICAH HOG MICAH.HOG@SBINFRACON.COM
  • MOLLIE BOSCAWEN MOLLIE.BOSCAWEN@STRAYFAMILY.COM
  • ROBIN PETER ROBIN.PETER@JUSTPLUMBIT.CO.UK
  • SILVIA GASKIN SILVIA.GASKIN@RSDRUKKERIJ.NL
  • TONY SCOWBY TONY.SCOWBY@RELATIVITYCOMPUTING.COM
  • VICKY GILLESPIE VICKY.GILLESPIE@CASAXALTEVA.ORG
  • VIOLET BAGBY VIOLET.BAGBY@JAMES-FOLEY.CO.UK
The following are examples of SHA256 hashes for the PDF attachments from Tuesday 2017-05-23:
  • 0218178eec35acad7909a413d94d84ae3d465a6ea37e932093ec4c7a9b6a7394
  • 0a326eb9a416f039be104bb5f199b7f3442515f88bd5c7ad1492b1721c174b8e
  • 21da9eeded9581f6f032dea0f21b45aa096b0330ddacbb8a7a3942a2026cc8ca
  • 4458f43127bb514b19c45e086d48aba34bf31baf1793e3d0611897c2ff591843
  • 66320f4e85e3d6bd46cf00da43ca421e4d50c2218cb57238abb2fb93bef37311
  • 7dd248652f2b42f3e1ad828e686c8ba458b6bb5b06cea46606ceccdd6b6e823c
  • 8a474cdd4c03dd4a6ba6ad8945bf22f74f2f41830203f846d5437f02292bb037
  • 956e43ece563fd46e6995fae75a0015559f0a63af5059290a40c64b906be5b9b
  • 9beb67a68396375f14099055b712e22673c9a1d307a76125186127e289ab41a2
  • b2b9c02080ae6fbe1845c779e31b5f6014ec20db74d21bd9dd02c444a0d0dd9b
  • c126e731c1c43d52b52a44567de45796147aca1b331567ed706bf21b6be936b4
  • cde2ff070e86bc1d72642cb3a48299080395f1df554e948fd6e8522579dfe861
  • daf01a1f7e34e0d47ecdfcef5d27b2f7a8b096b4e6bc67fb805d4da59b932411
  • e477300e8f8954ee95451425035c7994b984d8bc1f77b4ccf2a982bb980806fe
The following are examples of SHA256 hashes and file names for the embedded word documents from Tuesday 2017-05-23:
  • 084ee31e69053e66fafe6e1c2a69ffec015f95801ce6020f7765c56d6f3c23ff - PQQIDNQM.docm
  • 0855061389b62ec6a9b95552357ff7571ae5c034b304978a533c6cba06c3f9e8 - GYTKPVM.docm
  • 1f2598dc7a7b8f84307d8c2fa41f5550c320f8192cd41e50b47570d3836e6fcc - RNJSMOVS.docm
  • 2dbf9e1c412aa1ffd32a91043642eb9cc80772c87dbbce3dd098c57d917277fb - DLDD7LH.docm
  • 3f95a7eeb1965193a4e92862c10897e04708b37b793b8e45f890d019358214c0 - DC2ZPQ.docm
  • 56cd249ff82e9bb96a73262090bc6a299ead64d6c75161520e745c2066f22430 - KAR6WLU.docm
  • 795d8312749c122fa10a93c9f3aa1c0f4ffc081714c0ddb66c141334f8ef0633 - M4SQLA2.docm
  • 8906d10a48487d8240bddd0c0cb5c076e88104c86bdf871b0143d74b6df3cc98 - NQBCXP4.docm
  • 91aa966e837c4144a1294aa912a2162397f3a6df98cf336891d234e267cd919f - RNOHLIAFU.docm
  • 933fcc1bf90716abf7c4eaf29b520d2276df895fb4dd5a76be2a55028a4da94e - PCHLUPL.docm
  • a98782bd10004bef221e58abcecc0de81747e97910b8bbaabfa0b6b30a93b66b - Q1DOEY13.docm
  • ae244ca170b6ddc285da0598d9e108713b738034119bae09eaa69b0c5d7635f8 - TH1DZZPT.docm
  • bc0b2fbe4225e544c6c9935171a7d6162bc611a82d0c6a5f3d62a3f5df71cf8c - OLZNKWSOW.docm
  • c702deaa2fe03f188a670d46401e7db71628e74b0e5e2718a19e2944282e05cd - VUG3FBFO.docm
The following is the sample of Jaff ransomware I saw on Tuesday 2017-05-23: The following are URLs generated by malicious macros from the embedded Word documents. Theyre used to download the encoded Jaff ransomware binary:
  • billiginurlaub.com - GET /fgJds2U
  • david-faber.de - GET /fgJds2U
  • elateplaza.com - GET /fgJds2U
  • electron-trade.ru - GET /fgJds2U
  • fjjslyw.com - GET /fgJds2U
  • hr991.com - GET /fgJds2U
  • jinyuxuan.de - GET /fgJds2U
  • khaosoklake.com - GET /fgJds2U
  • minnessotaswordfishh.com - GET /af/fgJds2U
  • oliverkuo.com.au - GET /fgJds2U
  • pcflame.com.au - GET /fgJds2U
  • tdtuusula.com - GET /fgJds2U
  • williams-fitness.com - GET /fgJds2U
The following is post-infection traffic from my infected Windows host:
  • 185.109.147.122 port 80 - maximusstafastoriesticks.info - GET /a5/
  • rktazuzi7hbln7sy.onion (tor domain for the decryption instructions)
Final words Much of this malspam is easy to spot among the daily deluge of spam most organizations receive. However, this PDF attachment/embedded Word doc scheme is likely an attempt to bypass spam filtering. As always, if your organization follows best security practices, youre not likely to get infected. For example, software restriction policies that deny binary execution in certain Windows directories can easily stop this infection chain. Even without software restriction policies, the intended victim receives warnings from both Adobe reader and Microsoft Word during the infection process. So why do we continue to see this malspam on a near-daily basis? I suppose as long as its profitable for the criminals behind it, well continue to see this type of malspam. If anyone knows someone whos been infected with Jaff ransomware, feel free to share your story in the comments section. Emails, malware samples, and pcaps associated with the 2017-05-23 Jaff ransomware malspam can be found here. ---
Brad Duncan
brad [at] malware-traffic-analysis.net (c) SANS Internet Storm Center. https://isc.sans.edu Creative Commons Attribution-Noncommercial 3.0 United States License.
Categories: Security Posts

What did we Learn from WannaCry? - Oh Wait, We Already Knew That!, (Tue, May 23rd)

Tue, 2017/05/23 - 16:59
In the aftermath of last weeks excitement over the WannaCry malware, Ive had a lot of lessons learned meetings with clients. The results are exactly what youd expect, but in some cases came as a surprise to the organizations we met with.
There was a whole outcry about not victim shaming during and after this outbreak, and I get that, but in most cases infections were process failures that the IT group didnt know they had, these lessons learned sessions have contributed to improving the situation at many organizations. The short list is below - affected companies had one or more of the issues below:
1/ Patch
Plain and simple, when vendor patches come out, apply them. In a lot of cases, Patch Tuesday means Reboot Wednesday for a lot of organizations, or worst case Reboot Saturday. If you dont have a test the patches process, then in a lot of cases simply waiting a day or two (to let all the early birds test them for you) will do the job. If you do have a test process, in todays world it truly needs to take 7 days or less.
There are some hosts that you wont be patching. The million dollar MRI machine, the IV pump or the 20 ton punch press in the factory for instance. But you know about those, and youve segmented them away (in an appropriate way) from the internet and your production assets. This outbreak wasnt about those assets, what got hammered by Wannacry was the actual workstations and servers, the hospital stations in admitting and emergency room, the tablet that the nurse enters your stats into and so on. Normal user workstations that either werent patched, or were still running Windows XP. That being said, there are always some hosts that can be patched, but cant be patched regularly. The host thats running active military operations for instance, or the host thats running the callcenter for flood/rescue operations, e-health or suicide hotline. But you cant give just up on those - in most cases there is redundancy in place so that you can update half of those clusters at a time. If there isnt, you do still need to somehow get them updated on a regular schedule. Lesson learned? If your patch cycle is longer than a week, in todays world you need to revisit your process and somehow shorten it up. Document your exceptions, put something in to mitigate that risk (network segmentation is a common one), and get Sr Management to sign off on the risk and the mitigation. 2/ Unknown Assets are waiting to Ambush You A factor in this last attack were hosts that werent in ITs inventory. In my group of clients, what this meant was hosts controlling billboards or TVs running ads in customer service areas (the menu board at the coffee shop, the screen telling you about retirement funds where you wait in line at the bank and so on). If this had been a linux worm, wed be talking about projectors, TVs and access points today. One and all, I pointed those folks back to the Critical Controls list (https://www.cisecurity.org/controls/ ). In plain english, the first item is know whats on your network and the second item is know what is running on whats on your network. If you dont have a complete picture of these two, you will always be exposed to whatever new malware (or old malware) that tests the locks at your organization. 3/ Watch the News.
.... And I dont mean the news on TV. Your vendors (in this case Microsoft) have news feeds, and there are a ton of security-related news sites, podcasts and feeds (this site is one of those, our StormCast podcast is another). Folks that watch the news knew about this issue starting back in 2015, when Microsoft started advising us to disable SMB1, then again last year (2016) when Microsoft posted their Were Pleading with you, PLEASE disable SMB1 post. We knew specifically about the vulnerabilities used by Wannacry in January when the Shadowbrokers dump happened, we knew again when the patches were released in March, and we knew (again, much more specifically) when those tools went live in April. In short, we were TOLD that this was coming, by the time this was on the TV media, this was very old news. 4/ Segment your network, use host firewalls
In most networks, workstation A does not need SMB access to workstation B. Neither of them need SMB access to the mail server or the SQL host. They do need that access to the SMB based shares on the file and print servers though. If you must have SMB version 1 at all, then you have some other significant issues to look at.
Really what this boils down to is the Critical Controls again. Know what services are needed by who, and permit that. Set up deny rules on the network or on host firewalls for the things that people dont need - or best case, set up denies for everything else. I do realize that this is not 100% practical. For instance, denying SMB between workstations is a tough one to implement, since most admin tools need that same protocol. Many organizations only allow SMB to workstations from server or management subnets, and that seems to work really nicely for them. Its tough to get sign-off on that sort of restriction, management often will see this as a drastic measure. Disabling SMB1 should have happened months ago, if not year(s) ago. 5/ Have Backups
Many clients found out *after* they were infected by Wannacry that their users were storing data locally. Dont be that company - either enforce central data storage, or make sure your users local data is backed up somehow. Getting users to sign off that their local data is ephemeral only, that its not guaranteed to be there after a security event is good advice, but after said security event IT generally finds out that even with that signoff, everyone in the organization still holds them responsible. All to often, backups fall on the shoulders of the most Jr staff in IT. Sometimes that works out really well, but all to often it means that backups arent tested, restores fail (we call that backing up air), or critical data is missed. Best just to back it your data (all your data) and be done with it. 6/ Have a Plan You cant plan for everything, but everyone should have had a plan for the aftermath of Wannacry. The remediation for this malware was the classic nuke from orbit - wipe the workstations drives, re-image and move on. This process should be crystal-clear, and the team of folks responsible to deliver on this plan should be similarly clear. I had a number of clients who even a week after infection were still building their recovery process, while they were recovering. If you dont have an Incident Response Plan that includes widespread workstation re-imaging, its likely time to revisit your IR plan! 7/ Security is not an IT thing
Security of the assets of the company are not just an IT thing, theyre a company thing. Sr Management doesnt always realize this, but this week is a good time to re-enforce this concept. Failing on securing your workstations, servers, network and especially your data can knock a company offline, either for hours, days, or forever. Putting this on the shoulders of the IT group alone isnt fair, as the budget and staffing approvals for this responsibility is often out of their hands. Looking back over this list, it comes down to: Patch, Inventory, Keep tabs on Vendor and Industry news, Segment your network, Backup, and have an IR plan. No shame and no finger-pointing, but weve all known this for 10-15-20 years (or more) - this was stuff we did in the 80s back when I started, and weve been doing since the 60s. This is not a new list - weve been at this 50 years or more, we should know this by now. But from what was on TV this past week, I guess we need a refresher? Have I missed anything? Please use our comment form if we need to add to this list! ===============
Rob VandenBrink
Compugen (c) SANS Internet Storm Center. https://isc.sans.edu Creative Commons Attribution-Noncommercial 3.0 United States License.
Categories: Security Posts