Malicious PDF — malware analysis report

Static analysis result for SHA-256 d43db498553427f2…

MALICIOUS

PDF

86.5 KB Created: 2021-09-18 03:10:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 3ed56911907a458ef2a7fbfcb3866766 SHA-1: 95722009dd4dfa0e2af0ae71481ff675814a6016 SHA-256: d43db498553427f2a11d42becd0592148e49bdd3d1f83fc3f10ad5b4c60387b6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. While no scripts were explicitly extracted, the PDF structure and embedded URIs are indicative of techniques used to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://chcial.ru/uplcv?utm_term=proxy+list+piratebays PDF link annotation
    • http://cbcom.fr/ressource/site-image/files/vuxomenixaxagite.pdfIn PDF document text
    • http://www.kowel.com/ckfinder/userfiles/files/1631027766.pdfIn PDF document text
    • http://asztalosweb.hu/userfiles/file/xemolefuxiba.pdfIn PDF document text
    • https://przygodanaukrainie.pl/admin/ckfinder/userfiles/files/99784430260.pdfIn PDF document text
    • http://rtm-plus.ru/ckfinder/userfiles/files/91095597821.pdfIn PDF document text
    • http://nsfeed.com/_UploadFile/Images/file/10800046896.pdfIn PDF document text
    • http://bibrka-school.org.ua/ckfinder/userfiles/files/90978321519.pdfIn PDF document text
    • http://tkhomedeco.com/assets/uploads/ckedit/files/20210918053624.pdfIn PDF document text
    • https://cometgroupinternational.com/ckeditor/ckfinder/userfiles/files/pajukamog.pdfIn PDF document text
    • https://semagro-msw.ru/pics/images/file/31639379052.pdfIn PDF document text
    • http://chanakyaaerospacedefence.com/userfiles/file/riratemuzazekexegal.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613be82160d94---8387701395.pdfIn PDF document text
    • http://schoonhovensvrouwenkoor.nl/ckfinder/userfiles/files/4717729570.pdfIn PDF document text
    • http://lasfyy.com/uploadfile/file/20210911063550333.pdfIn PDF document text
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/161346f42f27b9---dazuwovu.pdfIn PDF document text
    • https://www.willmarareachamber.com/ckfinder/userfiles/files/90577624195.pdfIn PDF document text
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/312bd1a4acafdcb63f56ce62a141b1cb/83999544734.pdfIn PDF document text
    • http://huefpdf.org/upload/file/27196149751.pdfIn PDF document text
    • http://concilianavarra.com/userfiles/files/nolatigifelovitibafipetut.pdfIn PDF document text
    • http://orikon.net/Images_upload/files/fulepitigifanaxaj.pdfIn PDF document text
    • http://webinaris.org/ckfinder/userfiles/publics/files/3658845149.pdfIn PDF document text
    • http://noithatphathuy.com/Images_upload/files/66965637359.pdfIn PDF document text
    • http://mizuho-co.net/file/ck/files/97684963287.pdfIn PDF document text
    • https://taucaotoccatba.vn/images/news/files/geraronikozusenazun.pdfIn PDF document text
    • http://dcbestwings.com/uploads/files/tagurogusigevimuf.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_off0000f06d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF06D 10496 bytes
SHA-256: 6c8586a4f1e22af948f53638c3d352c0818b4346716df6083a599f1c312f053d
font_01_sfnt_off00010845.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10845 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012057.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12057 17000 bytes
SHA-256: 1e1e7ffb3e24c8f0b4b7ec0599f9ac18458f7f7c873e17c35fc9139ff85d9d35