Malicious PDF — malware analysis report

Static analysis result for SHA-256 b170ef25d3c88734…

MALICIOUS

PDF

106.5 KB Created: 2021-09-06 20:47:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: be48d163cbb87fd2a25737e79a2423fe SHA-1: ba07d3d0ac11f3c46176ae79081ba9aadba6d7e6 SHA-256: b170ef25d3c887347ce5924ce9419947982de023203cdd6c5347226e50529b1a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code or redirecting users. Multiple heuristics indicate the presence of link farms pointing to compromised websites and disposable hosting, suggesting a phishing or malware distribution campaign. The ClamAV detection and ML classifier further confirm its malicious nature, likely as a phishing lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://synerhu.ru/uplcv?utm_term=livro+felizmente+h%C3%A1+luar+pdf PDF link annotation
    • https://alshamiltrading.com/alshamilfiles/file/mumorosoja.pdfIn PDF document text
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f4af6d332f8---96610805774.pdfIn PDF document text
    • https://ajambary.com/userfiles/file/medewiwemuba.pdfIn PDF document text
    • http://3duct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e71e5be7aa---gebovovexibivazetugosez.pdfIn PDF document text
    • https://delphin-bau.com/ckfinder/upload/files/48094655073.pdfIn PDF document text
    • http://quimis.org/js/ckfinder/userfiles/files/lusakenosejobavebupogowu.pdfIn PDF document text
    • https://pasarangroup1.com/contents/files/tadazifuturekowofozulu.pdfIn PDF document text
    • http://southportrubbish.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074184a2af17---bopagiwufekulom.pdfIn PDF document text
    • http://nujhimachal.in/img/uploads/files/javupaxumipivoxisirofel.pdfIn PDF document text
    • http://preserveproperties.com/userfiles/files/2048629479.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f546064cba---moxivazugabesafipugabe.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1606eda980c4ec---56055025217.pdfIn PDF document text
    • http://niezapominajkowo.eu/userfiles/file/munuporiwefuxoz.pdfIn PDF document text
    • https://orkhaconstruction.com/wp-content/plugins/super-forms/uploads/php/files/0alki3p0je4c9aj9ttfbo6ut8s/lazukalakumitamazirof.pdfIn PDF document text
    • http://skuplaptop.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160bbb4a7a5dd1---bufosogalux.pdfIn PDF document text
    • http://ychnjl.net/userfiles/files/wutejefon.pdfIn PDF document text
    • http://www.umadai.com/ckfinder/userfiles/files/zofukovipisodawag.pdfIn PDF document text
    • https://www.traitagri-solutions-alternatives.fr/ckfinder/userfiles/files/barinonus.pdfIn PDF document text
    • http://liqaa-lb.com/files/userfiles/files/52563512288.pdfIn PDF document text
    • http://naturabliskociebie.pl/userfiles/file/43949717452.pdfIn PDF document text
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/60f53080ab86506b8335343419647b7e/94636591007.pdfIn PDF document text
    • https://mabuksusu.com/contents//files/voramota.pdfIn PDF document text
    • http://cityhighclassof77.com/clients/9/9e/9ea685038b5a197d2022a69b8c6b162a/File/85819357890.pdfIn PDF document text
    • http://cleannshieldflorida.com/wp-content/plugins/super-forms/uploads/php/files/75d518744e33a84a1310454035d53de6/fukejenoxoruwunom.pdfIn PDF document text
    • http://kruengrangthai.com/files/files/xetita.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_off00012f13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12F13 10960 bytes
SHA-256: 7025831fa98df2a66b2c027003182457db628372e5358b9fda22fc30a6aaa56b
font_01_sfnt_off000147da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x147DA 23256 bytes
SHA-256: c1caf6bb8cdaee62705c35cc4cabdbfec45302741093c96fb7f64fcd61dc04cc
font_02_sfnt_off000181e1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x181E1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1