Malicious PDF — malware analysis report

Static analysis result for SHA-256 4aef8fd82fb0669a…

MALICIOUS

PDF

78.8 KB Created: 2021-09-09 15:58:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 9f157ca5fcdcfa3071e494fd163d1c94 SHA-1: f566ccccb3774f8b0dcda266495eeb8da2879a55 SHA-256: 4aef8fd82fb0669aedc6682ba8bb63c8a13e5790af3f1e36c9b5e472d925bcf5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, forming a link farm. One notable URL is `http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613151604c8d0---bolovigudomoxarinawid.pdf`, which is part of a link farm strategy. The presence of PDF-specific heuristics like `PDF_SEO_DISPOSABLE_LINK_FARM` and `PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM` further supports the phishing and redirection attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://aow.infogestnet.it/ckfinder/userfiles/files/43563800827.pdf In PDF document text
    • http://ecohouse-lab.com/userfiles/file/53351707.pdfIn PDF document text
    • http://www.qookspot.kitchen/wp-content/plugins/formcraft/file-upload/server/content/files/1613938243f713---37525766866.pdfIn PDF document text
    • http://olymp-kiev.com/temp/fckeditor/file/sexawokunifunol.pdfIn PDF document text
    • http://kdwatch.net/upload/files/2021090714581667.pdfIn PDF document text
    • http://teifsepahan.com/files/file/zavewaroguxuma.pdfIn PDF document text
    • http://hutbephottaihaiphong24h.com/upload/files/89023539805.pdfIn PDF document text
    • https://flims.atelierleuthold.ch/userfiles/files/duxotenugopi.pdfIn PDF document text
    • http://snp-ent.com/files/fckeditor/file/909043246139c39b79183.pdfIn PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613151604c8d0---bolovigudomoxarinawid.pdfIn PDF document text
    • http://zhongjiukeji.com/upload_fck/file/2021-9-6/20210906032446423820.pdfIn PDF document text
    • https://2ruoteexpo.it/ckfinder/userfiles/files/retelon.pdfIn PDF document text
    • https://www.domaine-boussard-chablis.fr/ckfinder/userfiles/files/jibuwadituxatineg.pdfIn PDF document text
    • https://livstyle.ro/home/livstyle/public_html/uploads/files/5733564080.pdfIn PDF document text
    • https://gabinetpro.pl/kosmetyczka/krakow/files/36031623777.pdfIn PDF document text
    • https://valerart.com/ckfinder/userfiles/files/2225764997.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130959f7a6b9---93255428186.pdfIn PDF document text
    • http://cbcom.eu/ressource/site-image/files/69749867411.pdfIn PDF document text
    • http://galerie45.com/userfiles/file/xoxetoneze.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/revamizesifakonavobadalas.pdfIn PDF document text
    • https://zagorjeadventureteam.hr/files/wukonefuregososiralunafur.pdfIn PDF document text
    • https://magicdiscoradio.com/userfiles/file/19416824377.pdfIn PDF document text
    • https://mobisteelegypt.net/userfiles/file/98447886816.pdfIn PDF document text
    • https://bestcoloringpages.com/userfiles/file/xuwop.pdfIn PDF document text
    • https://xn--22ck6bdp5cach0mc23a.com/ckfinder/userfiles/files/22858063425.pdfIn PDF document text
    • http://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202109061131037047.pdfIn PDF document text
    • https://mimpishio.com/contents/files/viwawavi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/FevRqgeaUVY/uplcv?utm_term=one+ui+3.0+beta+download+apkPDF 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_off0000d0a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD0A0 10920 bytes
SHA-256: 380e7674d02ce30466a3254cb7510ba669e1daf53d6972bc237135ecada9eede
font_01_sfnt_off0000e9da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9DA 16756 bytes
SHA-256: 715a1cf8cc94c2904ba464f1b2a4f400b183fef75bdf89e710cd32d9897bd5c0
font_02_sfnt_off0001153a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1153A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1