Malicious PDF — malware analysis report

Static analysis result for SHA-256 d32e81456c86ece1…

MALICIOUS

PDF

84.4 KB Created: 2021-09-20 18:33:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 5d0c4f5a27b9202af0b50307d4c6797e SHA-1: dde7f7635c09b713f1376612e7ab6502e6d1bbf7 SHA-256: d32e81456c86ece196ca1a9789b0efa40017647b550a5c3cd6aece50983260d6
156 Risk Score

Malware Insights

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

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics indicate the PDF contains a link farm pointing to compromised WordPress upload storage and other disposable hosting, suggesting a phishing or malware distribution lure. The embedded URLs and the nature of the heuristics strongly suggest this PDF is used as a delivery mechanism for further malicious activity.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://syekp.gr/sites/default/files/file/49288007794.pdf In PDF document text
    • http://betonkeritesek.eu/Content/files/60059888538.pdfIn PDF document text
    • http://krzysztofmalec.pl/gfx/fck/file/gotizopefo.pdfIn PDF document text
    • http://eyupsifalibitkiler.com/resimler/files/bufimululikaza.pdfIn PDF document text
    • http://hzkontejnery.cz/ckfinder/userfiles/files/22811379810.pdfIn PDF document text
    • http://chicagohalo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161417dba9f89d---95558691939.pdfIn PDF document text
    • http://kesifveotesi.com/files/13276618280.pdfIn PDF document text
    • https://mountainbrookbuilders.com/home/mountain/public_html/ckfinder/userfiles/files/munefe.pdfIn PDF document text
    • http://moutierrozeille.fr/userfiles/file/vodilawadumalate.pdfIn PDF document text
    • http://surausa.com/uploads/files/judorutaviwakoxarafabo.pdfIn PDF document text
    • https://ibextrail.com/editor-images/84588853839.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16133dbae0a418---81210574983.pdfIn PDF document text
    • http://blccy.com/userfiles/files/pewijaverim.pdfIn PDF document text
    • http://mastera-mix.ru/ckfinder/userfiles/files/koketitizogosizosumuf.pdfIn PDF document text
    • https://namastehealth.in/wp-content/plugins/super-forms/uploads/php/files/uh9v7sjkt8ej48tutd4qaosf8d/subenasurijo.pdfIn PDF document text
    • http://ebd.su/UFD/7623/files/vumutuluxodipavusaluxu.pdfIn PDF document text
    • http://geofer.eu/userfiles/files/17942865182.pdfIn PDF document text
    • https://bike-accessories.supersites.gr/content/ckfinder/files/gefelekovodapi.pdfIn PDF document text
    • https://drhuanghair.com/uploads/files/202109031517327911.pdfIn PDF document text
    • https://petroblend.com/wp-content/plugins/formcraft/file-upload/server/content/files/16147a75b2f973---42519901449.pdfIn PDF document text
    • http://chinalabware.es/d/files/zusipet.pdfIn PDF document text
    • https://dolupin.com/calisma2/files/uploads/zaretelanopotox.pdfIn PDF document text
    • https://tiemhoamo.com/data/dulieu/files/kukepupubotamezijuraguzox.pdfIn PDF document text
    • https://genia-groupe.fr/images/files/kikidu.pdfIn PDF document text
    • http://santamariamikado.com/uploads/files/49606082797.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=new+zack+snyder+justice+leaguePDF 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_off0000e400.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE400 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fc17.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFC17 10984 bytes
SHA-256: 243cec04b7fe31d99cb9093eb8a17fd301781daed81207ce4dcc202f9b184061
font_02_sfnt_off00011596.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11596 17724 bytes
SHA-256: 055c8cf3e1de8c890c06220d5abc47b81be3e5465400e86ad277f89eab042a32