Malicious PDF — malware analysis report

Static analysis result for SHA-256 813de44d3bd35b01…

MALICIOUS

PDF

78.2 KB Created: 2021-09-13 22:31:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 6799bacb3c96e469b47f8f625894f39e SHA-1: 61ad70a2d96ba85d0f832b0f8004522b66e0211c SHA-256: 813de44d3bd35b01f77f2f15478f8d38e3488270e842f55586e2cf3488d73bdb
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to compromised websites or link farms, suggesting a phishing or redirection scheme. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' specifically indicates a pattern of using disposable hosting for link farms, reinforcing the malicious nature of the document's content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9958

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://broadstripe.com/wp-content/plugins/super-forms/uploads/php/files/0ae6d309bd74255e6e0fea78812489a6/95520086552.pdf In PDF document text
    • https://gcr.goldcrownresort.com/magazine_files/files/pujirisarabelisukefiwiwi.pdfIn PDF document text
    • https://www.kiakaha.gr/wp-content/plugins/super-forms/uploads/php/files/sk7h71euvnebd8bjc88rin71na/3623325331.pdfIn PDF document text
    • https://holocaustresearch.pl/nowy/photo/file/18302767098.pdfIn PDF document text
    • http://sportschoolindex.nl/images/uploads/tixitirisat.pdfIn PDF document text
    • http://mylodge-naoshima.com/images/blog/file/81403526982.pdfIn PDF document text
    • https://transturist.ba/ckeditor/ckfinder/files/files/tinene.pdfIn PDF document text
    • https://celebicatering.com/upload/ckfinder/files/49936020172.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cfa8fae08b---kerinitufez.pdfIn PDF document text
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d27b0311b5---nogikewejudivase.pdfIn PDF document text
    • https://winstar-tools.com/UserFiles/editor/file/topodojodutidudomedoduv.pdfIn PDF document text
    • https://pepinieramontana.ro/ckfinder/userfiles/files/73313729360.pdfIn PDF document text
    • http://zartmobilia.com/userfiles/file/20210904221129.pdfIn PDF document text
    • http://izhar-energy.com/userfiles/file/xavasawuxavulazoziwuxobam.pdfIn PDF document text
    • https://dagvandearchitectuur.be/_files/file/41299028718.pdfIn PDF document text
    • http://xn----ftbkdcamitb5h.xn--p1acf/files/fck/file/luwuvifawarinixarekobemor.pdfIn PDF document text
    • http://jeyadhurgatemple.com/userfiles/file/15802831237.pdfIn PDF document text
    • http://poexali.org/static/image/_u/system/files/84875740708.pdfIn PDF document text
    • https://mar3ol.com/Files/files/rateramulon.pdfIn PDF document text
    • https://gifarlcm.com/upfiles/editor/files/5638936572.pdfIn PDF document text
    • https://4cmedica.com/ficheiros_upload/file/8493803072.pdfIn PDF document text
    • https://marmetal.cevhertemizlik.com/userfiles/files/jatesepusikot.pdfIn PDF document text
    • http://inbiosa.eu/static/cfiles/files/57439130913.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=instagram+profile+profile+viewerPDF 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_off0000c19b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC19B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d9b2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9B2 10804 bytes
SHA-256: 367879a380e2bdec306da5c96ceca48ef6f71b5f6fc5650c86b977d7ddd78059
font_02_sfnt_off0000f2a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A1 21512 bytes
SHA-256: dd01db5edf2465dbd9eaecf5bf86a8021fedb2c74a5d496aae7c4772cac2d75b