Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9b78402e9a1f062…

MALICIOUS

PDF

78.5 KB Created: 2021-09-23 10:13:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 8606020686c5d7d96a27fb166b382c3d SHA-1: adaca9280f7247ae79e7c071aac8729454c4dc1e SHA-256: a9b78402e9a1f0621237245a92bd42d624254ac39d85858f5e6be8078dd3d32f
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm designed for malicious redirection. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the nature of the embedded URLs and the heuristic firings point towards a phishing or malware distribution scheme, likely initiated via a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://ketchas.ru/uplcv?utm_term=autocad+2018+serial+number+free PDF link annotation
    • https://lightupalife.org.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1614afa8cc0b42---68267268805.pdfIn PDF document text
    • http://ros.by/ckfinder/userfiles/files/35474343825.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/kereziwamajidexoxotusepan.pdfIn PDF document text
    • https://kitapkapla.com/upload/ckfinder/files/96843533515.pdfIn PDF document text
    • http://komputerzagrosze.pl/userfiles/file/tebedejetadimuzazewerek.pdfIn PDF document text
    • http://avtokit116.ru/!upload/files/26815082531.pdfIn PDF document text
    • http://licausi.it/userfiles/files/rezikojodorutu.pdfIn PDF document text
    • http://kxzyjy.com/CKEdit/upload/files/72844059104.pdfIn PDF document text
    • http://superfishinglewood.com/uploads/files/rizizimujalenesovofefiki.pdfIn PDF document text
    • http://softwarefactory.nl/images/file/33534011206.pdfIn PDF document text
    • http://dsagco.com/Upload/file/bemer.pdfIn PDF document text
    • http://dongduong.net/Images_upload/files/zuzapepelexew.pdfIn PDF document text
    • https://hotelharmika.com/assets/userfiles/files/71540629289.pdfIn PDF document text
    • http://connect-event.fr/ckfinder/userfiles/files/92709719388.pdfIn PDF document text
    • http://prodesign31.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613442e55db76---17926142921.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/fikizakisobujokowi.pdfIn PDF document text
    • https://barcelonacentremedic.cat/files/galeria/files/30462073591.pdfIn PDF document text
    • https://lufty.cz/UserFiles/files/23035146205.pdfIn PDF document text
    • https://ancoraeducacion.com/images/94891595252.pdfIn PDF document text
    • http://rhondachem.com/d/files/48650264486.pdfIn PDF document text
    • http://gtshotel.it/images/file/42298926341.pdfIn PDF document text
    • http://mebco.ru/images/file/fazewetaxeja.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136d6d6ea2c8---wuzejesopifekeviwolujaki.pdfIn PDF document text
    • https://s-serviss.lv/userfiles/file/duzasiliwakigunusel.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_off0000ce9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE9D 11360 bytes
SHA-256: ab01e51971b619c809a1893bfeb52bb3bfd7098736881c9beb3acf3d52b5a438
font_01_sfnt_off0000e972.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE972 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010184.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10184 16768 bytes
SHA-256: 0684ec6144196209272d471d895c0026dd4543bd03ea038c46ed891c9255a935