Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1c4eefc37e71cc4…

MALICIOUS

PDF

85.4 KB Created: 2021-07-04 14:53:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d4037579f16923a1d14949233b53628e SHA-1: 760c9291c76297a71c5698c19342be60089b17f3 SHA-256: b1c4eefc37e71cc47e87c71fac4ba1a284451fb05bc3684acf711a5a59306636
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to compromised CMS upload directories. These links likely serve as lures for phishing attacks or to distribute further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://licausi.it/userfiles/files/75563700172.pdf
    • http://cz-synergy.cz/data/file/sumirevinovevutaza.pdf
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a7d0f3c19c8---porebesosefarubiduwotek.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/j0l3jmncs4pic5re22gkv3nlul/vetin.pdf
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/e8d6bff2b5111c2478dd4c8d78bdd5fd/36189532528.pdf
    • https://dialogueinpraxis.net/files/docs/kutiranixotisosat.pdf
    • http://businessdevelopmentcenter.pl/uploads/userfiles/files/85509363303.pdf
    • https://aashianarealty.com/file/56574154873.pdf
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/irnj7s77ck1q9tnbtrml5jq9th/43541501830.pdf
    • http://chrislahoda.ca/userfiles/file/janepulifosigepadi.pdf
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/2c2925a6976a25823ed7eaed6b9842dd/witozapanuverovibuwagas.pdf
    • https://bdaudit.ro/userfiles/file/dijezomugijepemefubifido.pdf
    • https://smilepath.com.au/wp-content/plugins/super-forms/uploads/php/files/ee3fae9f923cd77a8a585de8dfeafb7c/rejadeleselativemes.pdf
    • https://vettercycles.ch/userfiles/files/mimejesab.pdf
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ad72bfaef9a---vukivonubatimukoja.pdf
    • http://hysansam.com/fckeditor/userfiles/image/52181663589.pdf
    • http://maekuangudomthara.com/ckfinder/userfiles/files/rupaxibixurirogowepalox.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/237f4c9078a96b82cda1aa523d2ce749/filope.pdf
    • http://ronaldtan.nl/images/photo/bopejukefogabanuzut.pdf
    • http://acril.ru/ufiles/files/jenipupegotolaxesaji.pdf
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160942bec585f7---68731741035.pdf
    • http://codemessaging.net/ckfinder/userfiles/files/95551883059.pdf
    • http://www.ellisrasbetonwerke.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16078986387fe8---givezadaxuwexujijevidoluw.pdf
    • https://rivaflo-south.in/userfiles/files/50615056543.pdf
    • https://benchmarktransitions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cab0037295---jevapij.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=the+cliff+walk
    • 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_off0000ef66.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF66 16792 bytes
font_01_sfnt_off0001077c.bin
6d473597b0f47638e7816d3721c585fb12e98f6cd05212bc85510e5360fa3347
pdf-font-stream PDF embedded font (sfnt) at offset 0x1077C 9984 bytes
font_02_sfnt_off00011dc2.bin
05fbf438981c11cd2759dc94bb42980785e4fc87f0b38db45c596338ed0147d6
pdf-font-stream PDF embedded font (sfnt) at offset 0x11DC2 16692 bytes