Malicious PDF — malware analysis report

Static analysis result for SHA-256 1aa603718e384942…

MALICIOUS

PDF

69.8 KB Created: 2021-09-22 13:47:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 39131cf79475579ede9413f93203797a SHA-1: 8df40f4d3e2a005c4cfe5cd7c1792b2c96a699f9 SHA-256: 1aa603718e384942c899654ec547174e0a7eba6287e9754edc70d8eb0c02ffad
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links, with several heuristics indicating it functions as a link farm, including directing users to compromised CMS upload storage. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://www.hon-ro.hu/userfiles/files/guvofoxapaturarolibodaze.pdf In PDF document text
    • https://biogenetixpharma.com/ci/userfiles/files/90224721153.pdfIn PDF document text
    • http://bagiez.com/userfiles/file/bukutowanobon.pdfIn PDF document text
    • https://cncostruzioni.com/userfiles/file/pelasomi.pdfIn PDF document text
    • http://cungcapbaoduongcuanhatban.com/upload/files/biresezugebakez.pdfIn PDF document text
    • http://svx.su/ffile/file/gazovogalelupu.pdfIn PDF document text
    • https://eniedu.com/data/file/20210910060620.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16145324fef1b3---66467100685.pdfIn PDF document text
    • http://studiogeologicotrilobite.com/userfiles/files/xebuwetexupidita.pdfIn PDF document text
    • http://agataklimowska.pl/userfiles/file/buvatesezomobisoripumiwu.pdfIn PDF document text
    • https://santechnikosdarbai.lt/images/files/6565130230.pdfIn PDF document text
    • http://hum-lucknow.org/test/fckeditor/file/78781123600.pdfIn PDF document text
    • https://paulogomeslda.com/userfiles/file/85723857391.pdfIn PDF document text
    • http://npi-management.com/ressource/site-image/files/5527638361.pdfIn PDF document text
    • https://gikguamerica.com/userfiles/file/71851441492.pdfIn PDF document text
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614aed8bb876d---62494099058.pdfIn PDF document text
    • http://perksys.com/userfiles/file/rejek.pdfIn PDF document text
    • https://eagleegg5k.com/ckfinder/triplebuserfiles/file/surirunisopisinakabevan.pdfIn PDF document text
    • http://capesociety.ca/uploads/files/batotijesibidepumaxuwa.pdfIn PDF document text
    • https://texigo.tw/upfile/files/2021/09/16/91333489058.pdfIn PDF document text
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/161320892231fd---roniturikemokuzagakefi.pdfIn PDF document text
    • https://tunguoilon.tunhua.vn/ipp/images/uploads/files/64178280577.pdfIn PDF document text
    • http://xn--ob0bjxt9h99icicrvkksa421cwwp7hiv4d6a.com/ckfinder/userfiles/files/4090878832.pdfIn PDF document text
    • http://www.recko.ru/ckfinder/userfiles/files/48946267350.pdfIn PDF document text
    • http://hauptlawoffice.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/tukidalipozitupibut.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=kendo+ui+angular+componentsPDF 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://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_off0000b20c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB20C 15240 bytes
SHA-256: fc1bc14919db833d2c6c25971751649f4f4eaec6e76580830554eaea351e964b
font_01_sfnt_off0000d882.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD882 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f099.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF099 10948 bytes
SHA-256: 1959c2875ab24179cdf86954d8425923c1f47c2a6de87b5d31dc4a0a89102f38