Malicious PDF — malware analysis report

Static analysis result for SHA-256 844dcaf03373e48c…

MALICIOUS

PDF

69.8 KB Created: 2021-09-09 06:55:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ea566c7cb4d5215ae3034a426efcb51a SHA-1: ea6c2982a5d17275650940eeaed15105ab76bbb2 SHA-256: 844dcaf03373e48ce1a9412ed2e185442db3f47a21104243e635ad3413e0371b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV and an ML classifier as malicious. It contains a link farm pointing to compromised WordPress upload storage and other disposable hosting domains, suggesting a phishing or malware distribution attempt. The presence of multiple external URIs and link farm heuristics indicates an effort to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://okfilm.kr/userData/board/file/8859421542.pdf In PDF document text
    • https://impariant-club.ru/wp-content/plugins/super-forms/uploads/php/files/d07d85fdb7b9453e9b99db5fc5fd0c23/38086776547.pdfIn PDF document text
    • http://quincy.pl/ckfinder/userfiles/files/90990976420.pdfIn PDF document text
    • https://mobile-translator.eu/app/webroot/media/files/19421851467.pdfIn PDF document text
    • https://bilalyapidekorasyon.com/userfiles/file/56972352672.pdfIn PDF document text
    • http://dok-vo.ru/userfiles/file/5700318417.pdfIn PDF document text
    • https://juvelyrikoscentras.lt/Files/file/kivuw.pdfIn PDF document text
    • https://retrofitoman.com/ckfinder/userfiles/files/16323825118.pdfIn PDF document text
    • http://fatamorgana.fr/uploads/assets/file/sezarotiso.pdfIn PDF document text
    • https://accu-split.com/userfiles/files/23554795304.pdfIn PDF document text
    • http://tuderprogettazione.it/userfiles/files/46395584472.pdfIn PDF document text
    • http://aodaibooking.com/FileData/ckfinder/files/20210904_CFC6CC45388AE01E.pdfIn PDF document text
    • http://www.marcelasemper.com/wp-content/plugins/formcraft/file-upload/server/content/files/161380f6cb406e---bilojuvilinugililatiwavov.pdfIn PDF document text
    • https://abouelhoulgroup.com/userfiles/files/76433622796.pdfIn PDF document text
    • http://btsoft.vn/uploads/files/tujogobalu.pdfIn PDF document text
    • http://imoroz.by/upload/file/tudotemanevakabarilal.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/16132a674d21cb---lagekijugibasukoz.pdfIn PDF document text
    • http://dakdekkersindex.nl/images/uploads/89296468187.pdfIn PDF document text
    • https://topinsolventa.ro/userfiles/file/lisanejawar.pdfIn PDF document text
    • https://booknowrentalimo.ch/userfiles/files/84119605563.pdfIn PDF document text
    • http://madiagranitosilano.it/userfiles/files/59254460829.pdfIn PDF document text
    • http://igabana.com/upfolder/e/files/20210906164354.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=v+words+to+describe+someonePDF link annotation
    • http://e1pl2.nazwa.pl/busy/fotki/file/jogasizisepawos.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_off0000b22d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB22D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA3F 15496 bytes
SHA-256: 479739c8d732359dd9a6876e0e891b7ee707fa35e0b73491e2de3aa01d8d0e18
font_02_sfnt_off0000f18a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF18A 10516 bytes
SHA-256: e378ed809db792d60b94e25049605b184f27cc0ead75eef1cdf27cd88e3e7efe