Malicious PDF — malware analysis report

Static analysis result for SHA-256 28782a12bea4f2ca…

MALICIOUS

PDF

93.8 KB Created: 2021-08-13 19:20:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 538e3eedbb480e46a8785ab742c93eba SHA-1: f0c95e51d97c404cb5ecab680f48dbf0ba049890 SHA-256: 28782a12bea4f2ca171610c2172585ab9d16e110b819e79273a17f209c11f43e
164 Risk Score

Malware Insights

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

The PDF document contains a large number of external links, many of which point to websites hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The document body itself is heavily obfuscated and does not provide direct textual clues, but the heuristic findings confirm the malicious nature of the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://webmodels.studio/wp-content/plugins/formcraft/file-upload/server/content/files/160729bebc5a32---kusopasexavonot.pdf In PDF document text
    • https://dispomydeal.com/wp-content/plugins/super-forms/uploads/php/files/1d5a71dcdc9a5f511fca5bee79683197/vikenagubakivafitodaruj.pdfIn PDF document text
    • https://deepankarbasu.com/FCKeditor/file/14015585806.pdfIn PDF document text
    • https://shriramsteels.in/public/ckfinder/userfiles/files/gemejepuporagobataw.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092b1c2e189a---dojejapojekewama.pdfIn PDF document text
    • http://techscreening.com/userfiles/files/29991651726.pdfIn PDF document text
    • https://hiddencliff.kr/FileData/ckfinder/files/20210803_7B6B3AC6D25CF1C4.pdfIn PDF document text
    • http://dalaichau.com/files/sanopob.pdfIn PDF document text
    • http://iworking.vn/uploads/files/15635212301.pdfIn PDF document text
    • http://gardensyellowcab.com/admin/images/file/sokukubo.pdfIn PDF document text
    • http://asu78.ru/userfiles/file/40012240085.pdfIn PDF document text
    • https://gamepinleri.com/calisma2/files/uploads/fodegurutazegawasako.pdfIn PDF document text
    • http://www.laterveer-biesenbeek.nl/ckfinder/userfiles/files/luvowejulure.pdfIn PDF document text
    • http://ms-krmelin.cz/app/webroot/files/files/95094927957.pdfIn PDF document text
    • https://emmaushuis.org/pages/wisidinaginimijek.pdfIn PDF document text
    • http://czechnews.cz/userfiles/files/disije.pdfIn PDF document text
    • http://ride.hu/images/uploads/files/jizosejeki.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160835a20662d1---vabidanisikojuf.pdfIn PDF document text
    • http://ilovegabal.net/fckeditor/_upload/file/64445347858.pdfIn PDF document text
    • https://opescom-store.com/uploads/FCK_files/file/72928308443.pdfIn PDF document text
    • http://makaifruits.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091a63422a51---17652862026.pdfIn PDF document text
    • https://ibeguiristain.com/userfiles/files/kikigokufogesopo.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/8aced0ce45d4b5f74021448ee0316dda/56860420479.pdfIn PDF document text
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609215d78b3e8---2181177743.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/160730e9602cc3---bawuzovalek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=free+movie+apps+for+android+tv+malaysiaPDF 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_off00010a87.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A87 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001229e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1229E 10816 bytes
SHA-256: 0eecf3ea8a95d13b025fa43421ea85fd08cd10f7e993bd9f0df2cc8cdb1df5fc
font_02_sfnt_off00013b92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B92 17016 bytes
SHA-256: b7729ea6231f556279d8e00b660cb3d8781a770e6135b60d431a2f6e5d80c1d0