Malicious PDF — malware analysis report

Static analysis result for SHA-256 a7c1009e63fee822…

MALICIOUS

PDF

86.5 KB Created: 2021-07-03 04:29:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 50c21f4cc8badb1c4bd40cb4490eb32e SHA-1: ea3c25b48f353ec28b043311cbf5231b4cd35d6d SHA-256: a7c1009e63fee8220730a3efd5a0025d2debdfe96cf64afd3af8f92af52ed490
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, containing numerous URLs that point to other PDF files hosted on compromised CMS upload directories. The primary purpose appears to be directing users to potentially malicious content hosted on these compromised sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/7960c3264c995e110e2409a9e1def5e3/22999268533.pdf
    • http://fulepmark.hu/nyebu/fulepmark/userfiles/file/76767764392.pdf
    • http://erex.hu/upload/file/gatakewugum.pdf
    • http://fobosgrunt.ru/files/ckfinder/files/73820642195.pdf
    • http://studiotecnicoprato.eu/userfiles/files/mevujujiwovore.pdf
    • http://olversonfamilyreunion.org/clients/5/51/51a48c89da211807e19ed56f8a1a1822/File/42187331952.pdf
    • http://vincityhomes.vn/wp-content/plugins/super-forms/uploads/php/files/k3vtf6cjdt4jn981jcgat4mb5e/57595125465.pdf
    • https://lynnesnaturaltreats.com.au/wp-content/plugins/super-forms/uploads/php/files/5d8111cec4d41d7dc6bb7d99830673ed/254176696.pdf
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a70d07d50e6---32149167914.pdf
    • https://chokysitohang.com/Uploads/userfiles/files/kolilabamujavirigel.pdf
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080e195ac793---jelikaxonitupim.pdf
    • http://bhk-aindling.com/userfiles/files/69108810829.pdf
    • https://shared401k.com/wp-content/plugins/super-forms/uploads/php/files/695d741681096b117b6785425961d8ae/tojexupudufopevurugoxep.pdf
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607183cbdceb1---zakudokelipumirari.pdf
    • http://rlangkhan.com/upload/userfiles/files/ximuzi.pdf
    • http://www.rebranded.tv/wp-content/plugins/formcraft/file-upload/server/content/files/16077bb6a9ba33---vuronude.pdf
    • https://its-bulgaria.bg/files/file/mameramizagonugiwabudasa.pdf
    • https://thepetrichortouch.com/wp-content/plugins/super-forms/uploads/php/files/iom7o4435v1hbjsv25sccnnb1v/19518108791.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=conditional+sentences+type+0+and+1
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e1e0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE1E0 16792 bytes
font_01_sfnt_off0000f9f7.bin
47e483c1d42423a065f8d03e9d00889f62e55abe4aa4339fd8ceeebc3dc7429b
pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F7 10724 bytes
font_02_sfnt_off000112cc.bin
78c9f2b0890d56d5410314a62fa9e6be0019f24b3015c39b3d29e82d7ea60f66
pdf-font-stream PDF embedded font (sfnt) at offset 0x112CC 22636 bytes