Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3852bc1991d2136…

MALICIOUS

PDF

87.1 KB Created: 2021-08-01 23:53:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 7d8114720ecdc963c8907be5b8262a35 SHA-1: 39b2a05b292ea72e929eb8857fc224d3734d6e19 SHA-256: a3852bc1991d21368394fdb8c42a8977c77dc62e11f40a3fe4de6ce7ad5141f7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1055.012 Process Injection

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Several heuristics indicate the PDF contains a link farm pointing to compromised WordPress upload storage, suggesting an attempt to distribute malicious content or phish users. The presence of multiple unknown URLs further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

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://elitestrategyglobal.com/wp-content/plugins/super-forms/uploads/php/files/b4a6226d0ec11e98ba575153ac33823c/rewalomanaperizasuwufoja.pdf In PDF document text
    • http://timebank.ru/sites/default/files/photos/pagefile/79096049748.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094553aee716---xuwomuzivuxuwusetuk.pdfIn PDF document text
    • http://avstralianature.ru/ckfinder/userfiles/files/jagiwogamosoze.pdfIn PDF document text
    • http://abwrva.com/uploads/files/wudikogavobojav.pdfIn PDF document text
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/42ffba4778ec5b03769fc08e1806c96c/14049011815.pdfIn PDF document text
    • http://aftckwt.com/uploads/file/larabipadunefuzix.pdfIn PDF document text
    • http://cosmik-kinoteatr.ru/sadm_files/943252646.pdfIn PDF document text
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16071494c0bde4---bibivijadivodaveguzesizi.pdfIn PDF document text
    • http://flexa.cz/docs/file/90779554522.pdfIn PDF document text
    • https://ashleymongolia.mn/uploads/files/duguxivomebemuxo.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f1d575baf9b---nuzabowoxovaluwaxujigu.pdfIn PDF document text
    • http://tootingtaxi.com/survey/userfiles/files/28999805927.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16076dc6964bfa---bipapagavubo.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/86751219529.pdfIn PDF document text
    • https://dm288.com/slicice/file/jopakilasaf.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609817f769e61---beneledo.pdfIn PDF document text
    • http://meyergarden.com/ckfinder/userfiles/files/11314796714.pdfIn PDF document text
    • http://moveisgarciadigital.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c886849a084---movuzerewezoku.pdfIn PDF document text
    • http://srihemkuntsahibfgp.org/hemkunt/userfiles/file/77273860138.pdfIn PDF document text
    • http://www.peplex.it/wp-content/plugins/formcraft/file-upload/server/content/files/16071657292dd8---29477007966.pdfIn PDF document text
    • http://chieusangducphat.com/uploads/userfiles/file/xaduwidisor.pdfIn PDF document text
    • https://amadesafar.ir/basefile/amadesafarir/files/33107752394.pdfIn PDF document text
    • https://bursakaynak.net/userfiles/file/xojasesuma.pdfIn PDF document text
    • http://www.appsolutely.sg/wp-content/plugins/formcraft/file-upload/server/content/files/16092834ca25ed---60643531057.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/rjfeass9de85ejekddtqlduns4/muverasuxaz.pdfIn PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/sfobm2q732jgn2549ihc5qfj7c/kibimor.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=lactic+acid+fermentation+glycolysisPDF 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_off0000f0a1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0A1 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000108b3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108B3 16864 bytes
SHA-256: cb99e70d4fcd4513d21628d6b09aa1cb45ed31cf94065f463b890523e4da691e
font_02_sfnt_off000134f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134F2 10892 bytes
SHA-256: 7070733444fe8f4d97908b00f9429d72658a84cd91b00468f8e6373704ee962c