Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c4d0b610d63af48…

MALICIOUS

PDF

82.3 KB Created: 2021-09-09 16:44:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: a837f00c1029222d5b023afa00c39c17 SHA-1: 157b959ee56c9ddaa8564c2c29ac779448279a5b SHA-256: 8c4d0b610d63af48e9ea6498a762dff24ba7e39aecafa26ccd78411a9ca8267d
156 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to lure users to malicious sites. The presence of a link farm on potentially compromised CMS uploads suggests an attempt to distribute phishing content or malware.

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 https://cochleartudaskozpont.hu/files/ledowigaxo.pdf In PDF document text
    • http://nakajima-ya.com/upload/save_image/files/mulele.pdfIn PDF document text
    • https://stmpallet.com/ckfinder/userfiles/files/kapivobojosusolar.pdfIn PDF document text
    • https://paardenwelzijnscheck.nl/app/webroot/files/ckeditor_files/files/kagofamaduto.pdfIn PDF document text
    • https://implantsdentairesdesmoulins.com/upload/editor/file/71371608457.pdfIn PDF document text
    • http://expnavi.com/sites/all/sites/default/files/file/pufupojaxifedapiz.pdfIn PDF document text
    • https://totounited.com/contents/files/fexewepunakokowidifuzevu.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/3dnb2702j6kkc63lqbsv6vlmp0/56437389024.pdfIn PDF document text
    • http://www.fotografoeventimilano.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133ae47efc40---rujedefa.pdfIn PDF document text
    • https://goodmix-psc.com/userfiles/files/97709571101.pdfIn PDF document text
    • https://herfection.herfection.tw/upload/ckfinder_temp/files/20210908065641.pdfIn PDF document text
    • http://kasand.com/userfiles/nafepobexipewuva.pdfIn PDF document text
    • https://hgindustrial.eu/userfiles/files/lesexikajejejaxosono.pdfIn PDF document text
    • http://nickels.design/ckfinder/userfiles/files/magonupawinawirotabo.pdfIn PDF document text
    • http://4darchitecture.org/img/all/37327749308.pdfIn PDF document text
    • https://www.medicalbi.com/ckfinder/userfiles/files/jijebofoke.pdfIn PDF document text
    • http://escritacontabilidade.net/fotos/news/file/31644869240.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16136789981d4e---56059087135.pdfIn PDF document text
    • http://cheapmarkt.com/userfiles/file/91904464153.pdfIn PDF document text
    • http://medwin.kr/userData/board/file/33134937350.pdfIn PDF document text
    • http://photou.cc/ckfinder/userfiles/files/bupojunaxovufamodenusinel.pdfIn PDF document text
    • http://tatugigo.com/ckfinder/userfiles/files/66296801169.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=mx+player+tv+download+for+android+tvPDF 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_off0000dce5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCE5 17884 bytes
SHA-256: 7c8a2cde7e15dd7cc6b46fe8d219984f1c8563faac35d81c0936e9bd8c134c53
font_01_sfnt_off00010ab8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AB8 10684 bytes
SHA-256: 98882fc5309c69c71cb33ecf60a23f98de3b1b91e954de0f0cdec6e4c68a8eff
font_02_sfnt_off0001236c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1236C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1