Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4ab9912a3685835…

MALICIOUS

PDF

90.0 KB Created: 2021-07-08 11:46:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ab4478aef7f013dc567bfe782ccbed0d SHA-1: eda9282dd85c6e912314a70dad26d338d02f73e4 SHA-256: f4ab9912a3685835e822d5a601f35cdbc2b7dbb55aa17d3a2c5ca192787027ad
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on compromised WordPress instances or disposable domains, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of embedded URLs and link farms points towards an effort to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9961

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://romangruszecki.com/uploaded/file/95680762988.pdf
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aaaa8c0b879---23846969688.pdf
    • https://kachhiproperties.com/wp-content/plugins/super-forms/uploads/php/files/kf6j44cb85dpn6rhetu2jvcbr6/ruridafutuvozejagiwade.pdf
    • http://www.hypnotiseur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac8b4bd87e9---385062623.pdf
    • https://grupo-kayros.com/userfiles/file/zodusederaduxamipa.pdf
    • http://altinellerinsaat.net/UserFiles/file/fogaduleforebu.pdf
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077f85deec26---litutepevefovunotod.pdf
    • http://bularz-auto.pl/images/userfiles/file/31839948230.pdf
    • https://www.andeanskyline.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d359065f832---muxozofuwodavagab.pdf
    • https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/94ndge7rvtr3dkbp3fc7u6k7o0/42378633982.pdf
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/e65b1f5ac0989e69d8e6a86ace13aa49/futurubiloxagomaxuna.pdf
    • http://flirtproducties.nl/ckfinder/userfiles/files/biwalaselisu.pdf
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/6e7ca283b94dd15309addebe0079db60/pikabupejakudusu.pdf
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/1915b4402b18ef93432730223f5f1861/vurizorifane.pdf
    • https://mmagame.com/userfiles/file/55360577111.pdf
    • https://414movement.com/wp-content/plugins/super-forms/uploads/php/files/251387a2b3a27e1c9dd169d3d7452e7d/84205968781.pdf
    • https://vigiweb.cl/dinamicos/files/file/45793357980.pdf
    • https://xn--80aaa1arbfjoe3bzh.xn--p1ai/data/files/dumamokide.pdf
    • http://artistalexanderkanevskywinnerinternationalaward.com/clientMedia/file/51693167328.pdf
    • https://naseeha.org/wp-content/plugins/super-forms/uploads/php/files/34ca06a309dc0dba43224a106c33a4f0/vulowimefelejezobegavigi.pdf
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/6fa3e6d6d8749678058b99e8f1ad3cc8/nozixunutokukizalufi.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=run+linux+from+usb+on+chromebook
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b03e4d5f33---mudurunesuze.pdf
    • 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_off0000fcc1.bin
b172a2966bf31c04683f1fa46491ee7b9f55d468cb5f97a106c47ac8c6f7f054
pdf-font-stream PDF embedded font (sfnt) at offset 0xFCC1 10820 bytes
font_01_sfnt_off00011588.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11588 16792 bytes
font_02_sfnt_off00012d9a.bin
6936a7004d1414e8877e38d2637aa768e2971c5af46ac164734fd6d70dad8280
pdf-font-stream PDF embedded font (sfnt) at offset 0x12D9A 16592 bytes