Malicious PDF — malware analysis report

Static analysis result for SHA-256 acd38611f7e585db…

MALICIOUS

PDF

70.7 KB Created: 2021-09-26 02:04:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: fdd268f738711dfda6b4e71d3cc1a669 SHA-1: fa81d6b12c26ab4ba106510a4d98d176cd3870c8 SHA-256: acd38611f7e585db1223b11878e89227efc780f147932fc97869a4bba54b647b
126 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which are hosted on disposable domains and appear to be part of a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. The presence of external URIs and the link farm heuristic suggest the document's primary purpose is to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://queure.ru/uplcv?utm_term=psp+emulator+for+android+apk PDF link annotation
    • https://rcot.org/userfiles/file/22938780433.pdfIn PDF document text
    • http://chieusangducphat.com/uploads/userfiles/file/kalunadiperakuful.pdfIn PDF document text
    • http://fszhenjia.com/upfolder/e/files/20210926065651.pdfIn PDF document text
    • http://vinacafe-dalat.com/Images_upload/files/watepez.pdfIn PDF document text
    • http://mama-care.com/UserFiles/file/2527947842.pdfIn PDF document text
    • http://skiflogistics.ru/userfiles/file/fawapajotoke.pdfIn PDF document text
    • http://ddservice-bmw.pl/userfiles/file/puvipefuverikuniworetu.pdfIn PDF document text
    • http://zuche0551.com/upload/file/49030540396.pdfIn PDF document text
    • https://fallahi-sch.com/userfiles/file/2540221862.pdfIn PDF document text
    • http://hataylezzeti.com/resimler/files/jekivu.pdfIn PDF document text
    • http://kursverwaltung.fit-n-essen.ch/ckfinder/userfiles/files/53441998375.pdfIn PDF document text
    • http://all-paca.com/ckeditor/ckfinder/core/connector/php/uploads/files/27979013426.pdfIn PDF document text
    • http://bagiez.de/userfiles/file/zebarezonesezebik.pdfIn PDF document text
    • http://nuklearmedizin-amro.de/userfiles/file/49491119744.pdfIn PDF document text
    • https://agrimal.pl/userfiles/file/lebofedojivuzalimager.pdfIn PDF document text
    • http://geteffective.biz/uploadfiles/file/69464286.pdfIn PDF document text
    • http://bookblog.kr/data/file/files/94961208775.pdfIn PDF document text
    • http://parcroyale.hk/userfiles/doxeveponedax.pdfIn PDF document text
    • http://arredamenticucinesiciliane.it/userfiles/files/rujinafupuzovul.pdfIn PDF document text
    • http://gopherandsquirrelcontrol.com/admin/images/file/ninumefovudunujanosiz.pdfIn PDF document text
    • https://www.mercato.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1613be48616440---50364176336.pdfIn PDF document text
    • https://cvsc.co/userfiles/file/71029182509.pdfIn PDF document text
    • https://adfaveo.com/image/files/20210924_211633.pdfIn PDF document text
    • http://bainihu.com/upfiles/editor/files/bewowovorubojobamivuxipe.pdfIn PDF document text
    • https://www.marthatrotts.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161495722d0b5c---64917450511.pdfIn PDF document text
    • http://xn----1-6cdapb2bdyqawnpcindqfc.xn--p1ai/media/file/dipafowaxep.pdfIn PDF document text
    • http://smsalumni1971.com/apadmin/uploads/userfiles/files/33652671769.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_off0000b36e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB36E 10852 bytes
SHA-256: 4fa0686ace9fab63864f2ff0a8f0984eb360178a1e5a295c1e968c694c30b362
font_01_sfnt_off0000cc80.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC80 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e492.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE492 16020 bytes
SHA-256: 97e61b5ff1b0436c254838d5b8edef4bb15bbbf621ba94769e7cb028e6e15059