Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c41580147cd123b…

MALICIOUS

PDF

81.3 KB Created: 2021-09-17 13:13:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 56d8491664e18bb6316dc3777c38f822 SHA-1: 35561a4cc4938ce13028cc592f457f9b2bb636e0 SHA-256: 8c41580147cd123b25399911778a96a16625199c46f8644893f22797c00938be
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link farm pointing to multiple external URLs, many of which are hosted on potentially compromised websites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution. While no scripts were directly extracted, the PDF structure and embedded URLs suggest an attempt to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://nsdadventist.org/FCKData/file/18402306698.pdf In PDF document text
    • https://latrinquette.com/upload/editor/file/vagolejavuf.pdfIn PDF document text
    • https://observatoire-omic.org/documents/file/zorivikolumekad.pdfIn PDF document text
    • http://dieutrimun.myphamkangnam.vn/webroot/img/files/7364255279.pdfIn PDF document text
    • http://chapaconoticias.com/assets/ckfinder/core/connector/php/uploads/files/7534950268.pdfIn PDF document text
    • https://dolnoslaskialarmsmogowy.pl/imgturysta/files/16554402599.pdfIn PDF document text
    • http://datavincity.com/uploads/ckfinder/files/52046893707.pdfIn PDF document text
    • http://kanizsakran.hu/userfiles/file/2873694817.pdfIn PDF document text
    • https://nexusmediation.nl/files/94887918214.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/16140828bcbf5e---roluzulimeveduro.pdfIn PDF document text
    • http://gzhangqin.com/uploadfile/files/60062601851.pdfIn PDF document text
    • https://eminentland.com/admin/userfiles/files/wozowibusele.pdfIn PDF document text
    • http://hoadon-dientu.net/images/files/xepopuvirumekelabuvet.pdfIn PDF document text
    • https://at2-turbo-j3t.com/contents/files/1707413838.pdfIn PDF document text
    • http://bftt.marketsearching.com/upload/files/90490515277.pdfIn PDF document text
    • https://akanaymatbaa.com/calisma2/files/uploads/xojiniwikiwebasumaje.pdfIn PDF document text
    • https://www.baptistenhardenberg.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16143186698962---roganizuwixujup.pdfIn PDF document text
    • http://preiswerte-unterkunft-papenburg.de/mediapool/35406536923.pdfIn PDF document text
    • http://silverk.ru/img/lib/file/jujaxupez.pdfIn PDF document text
    • http://xn--80aaa6aachkjln0qra.xn--p1ai/ckfinder/userfiles/files/49850954600.pdfIn PDF document text
    • http://ristoranteibucanieri.it/userfiles/files/dizetokixatuvagokamamenoj.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614199a6ae683---22512825320.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=how+to+open+a+pages+file+on+androidPDF 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_off0000d79c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD79C 18104 bytes
SHA-256: 165dc875a593ccc4988aa19939fd4d89f363b883e595dfee49b79500c526b18a
font_01_sfnt_off000106cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106CB 10748 bytes
SHA-256: 239c53a18850c8c58277863de103d80e2c1b758363b4d789bffc8baba522a610
font_02_sfnt_off00011f74.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F74 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1