Malicious PDF — malware analysis report

Static analysis result for SHA-256 557fc907e4c194c0…

MALICIOUS

PDF

142.0 KB Created: 2021-06-20 15:47:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 72d333314c95e61009c4e218da6bc735 SHA-1: 83666ac920bb7ab5af2f359fb8c9aa1e629de1b5 SHA-256: 557fc907e4c194c0a22cb6de98953e42c2a9cefca22a42f1c35af46f374a93d2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous links pointing to compromised WordPress upload directories and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the overall structure indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://www.nestroots.com/wp-content/plugins/super-forms/uploads/php/files/263nu93ihcg7boac1ki9rvjrb4/ximinigewifapulabejofutis.pdf In PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/5063ebc8be3a0333b043878fab7a8c01/72785035137.pdfIn PDF document text
    • http://omg.su/upload/File/43018538383.pdfIn PDF document text
    • http://mini-garden.ru/userfiles/file/58971928252.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/0b8598106330f2133fe16cddc305a315/ramililonajekirazugade.pdfIn PDF document text
    • http://coinproject.com/userfiles/image/file/vopitiwulujixetusafik.pdfIn PDF document text
    • https://k9-warrior.com/wp-content/plugins/super-forms/uploads/php/files/r11o2qnotj5721vr8mqnr5m9cb/98745745850.pdfIn PDF document text
    • http://szpital-sulecin.pl/images/fckfiles/file/44509470905.pdfIn PDF document text
    • http://www.rec39.ru/wp-content/plugins/super-forms/uploads/php/files/b819e82f6f2c42c074ad68f64bded5a9/wujukudozi.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/2ojceo38vflrf1290e5o60ecco/51662284077.pdfIn PDF document text
    • https://powermailer.in/userfiles/file/surivusefogumokibirosoxij.pdfIn PDF document text
    • https://alshaabcoop.com/userfiles/file/dulamamegadegabab.pdfIn PDF document text
    • https://criteriacambio.com.br/wp-content/plugins/super-forms/uploads/php/files/6nduq5f3nlokqpgc2obat51pb3/saxubamikupomudanirisuduw.pdfIn PDF document text
    • http://arcdesantmarti.com/biocop/Images/images-editor/file/gekubigo.pdfIn PDF document text
    • https://noddy.nu/images/file/90122762734.pdfIn PDF document text
    • https://gradeagroup.com/wp-content/plugins/super-forms/uploads/php/files/m2k33shdnjg3mlvnefdc3tqfse/88600160231.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=lesbian+mom+seducing+daughters+friendPDF link annotation
    • 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001eb89.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1EB89 5484 bytes
SHA-256: e71770bc307836d7a8e9f7d67d767d16fc4a6ba17841e7a12561dd20ef5fd392
font_01_sfnt_off0001fe06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1FE06 14928 bytes
SHA-256: f05892ed7421e8378b6f8b024b94688d3e2ca15c2e30db1098ce38e7081b6e33