Malicious PDF — malware analysis report

Static analysis result for SHA-256 4319b88e817f7597…

MALICIOUS

PDF

111.8 KB Created: 2021-09-04 07:07:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 920739caf369bcc51d8ea110f6d20383 SHA-1: 234aa6dcbd80a4379f7336f47b3cb74352977772 SHA-256: 4319b88e817f7597e7f9443f8846f47bbbdb60fe93a996952825b7914ed12b62
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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 https://coretry.ru/uplcv?utm_term=plato+the+republic+pdf+benjamin+jowett PDF link annotation
    • http://hitecds.com/userfiles/file/toguremajijofemagivenonu.pdfIn PDF document text
    • http://ccswcd.com/userfiles/file/46447173379.pdfIn PDF document text
    • http://smepil.com/ckeditor/userfiles/files/litidusiwodavaguj.pdfIn PDF document text
    • https://scapetime.net/images/website/user/files/6154590211.pdfIn PDF document text
    • https://grancom.by/upload/docs/88264967271.pdfIn PDF document text
    • http://theartofdesign.nl/ckfinder/userfiles/files/zidid.pdfIn PDF document text
    • http://pjteam.hu/uploads/93170207688.pdfIn PDF document text
    • https://elminhaj.org/userfiles/file/10979700674.pdfIn PDF document text
    • https://pass-eco-energies.com/ckfinder/userfiles/files/juseletonutopudo.pdfIn PDF document text
    • http://www.niziointerior.pl/upload/file/tevuwetatiroguk.pdfIn PDF document text
    • https://tresonance.org/uploadfiles/28458279646.pdfIn PDF document text
    • http://www.wallisandemmanuel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160841bca0eb8e---tetusilevevunotolovogifu.pdfIn PDF document text
    • http://iuf.kr/pds_down/files/74443608530.pdfIn PDF document text
    • http://dentherapia.hu/files/file/jojigimifova.pdfIn PDF document text
    • https://limsurdua.com/contents//files/56824890101.pdfIn PDF document text
    • http://xn--b1ahhafccpgkb2bxo.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/42650482e2e57c94dc8ff9df85672f26/fawofudolinajurit.pdfIn PDF document text
    • http://3handseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608050b602185---94421112303.pdfIn PDF document text
    • http://rivieahk.com/clients/5/51/51325344bd1517f257d6959d5350918e/File/82292453485.pdfIn PDF document text
    • https://www.ideaklinikizmir.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075581360e83---47719288535.pdfIn PDF document text
    • http://otpetye.com/images/shared/file/21889857240.pdfIn PDF document text
    • https://alternatifhirdavat.com/upload/ckfinder/files/dejitamilukuli.pdfIn PDF document text
    • http://www.moyekolodin.com/files/7693815777.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160d20cdcd38c2---72665324799.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000147ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147FF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00016011.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16011 21392 bytes
SHA-256: 9089f20615a9ace7912f4a52ceb2e3e22ea931d1329db038d425688626bef2d8
font_02_sfnt_off0001974e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1974E 11172 bytes
SHA-256: daa7367f5ae2b5600ee034ee530b240d0104bb9a5d179507bb548468094ac134