Malicious PDF — malware analysis report

Static analysis result for SHA-256 509258250b8645f2…

MALICIOUS

PDF

81.4 KB Created: 2021-09-04 06:06:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 939c842f7c92c5498709d1de90da3577 SHA-1: c97616bd083275fa659e7f8e182ad02e5d65a542 SHA-256: 509258250b8645f28f9be76f2578a6db158a76d7628b9e52a84d5a7ff79c4828
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. Heuristics reveal it functions as a link farm, with many embedded URLs pointing to compromised CMS uploads and disposable hosting. The document body is unreadable, but the URL structure and heuristic firings strongly suggest a phishing attempt to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://decamiones.com/userfiles/file/57694370730.pdf In PDF document text
    • https://australiancaravancentre.com.au/application/third_party/ckfinder/userfiles/files/linofukolefox.pdfIn PDF document text
    • https://www.sehersirin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d8eb5d1db9---67242086013.pdfIn PDF document text
    • http://pphu-joanna.pl/fckpliki/file/bifemefusadatunapatijo.pdfIn PDF document text
    • http://salondebellezaanamariaromero.es//ckfinder/userfiles/files/26519295332.pdfIn PDF document text
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/901e1ba96e3e06ca60e808a5dfbcd41b/49937000932.pdfIn PDF document text
    • https://facade-metal.ch/ckfinder/userfiles/files/92665513838.pdfIn PDF document text
    • https://investmentskillsgroup.com/images/userfiles/file/tovebidosubuxu.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608d71082e533---bojulagoremefuf.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/a0ae24d0cf4f130a9296a87121741faa/31560920854.pdfIn PDF document text
    • http://resetimpianti.it/reset/public/file/80386206653.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/a02cf71f23241ac7a8e527f8c7f813aa/81044317106.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160acd5bfcd7c5---danemerafofitimos.pdfIn PDF document text
    • https://hohsingfiber.com/ufiles/files/80238692634.pdfIn PDF document text
    • http://stphilomenaonline.org/userfiles/file/13049613286.pdfIn PDF document text
    • http://www.alfapilates.pl/upload/file/saselimaxilufis.pdfIn PDF document text
    • http://ambulanceservice.pl/userfiles/file/fekasagalaxat.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=it+changed+my+life+betty+friedan+pdfPDF 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_off0000dbaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBAF 17236 bytes
SHA-256: 7574bf236dd1d5277e740dc168bfde168370c54c6bde7bdce9506b538aacbf62
font_01_sfnt_off000107c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107C7 10984 bytes
SHA-256: 63497c1be66af9332abd3b72a04b4e38c0eae023bf1f2ebeb08e0ba9284ef04c
font_02_sfnt_off000120a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120A0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1