Malicious PDF — malware analysis report

Static analysis result for SHA-256 0c83c90b5d420a43…

MALICIOUS

PDF

76.9 KB Created: 2021-06-26 05:03:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 743296b048f9094293bedce466bf88e0 SHA-1: 5493272764dc5eb28bb77fed67d459e1d8dc04d0 SHA-256: 0c83c90b5d420a43809b9067f2827c3df7f8b9a7b0436338cf8ef6a95cd06bd8
156 Risk Score

Malware Insights

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

The file is a PDF containing a large number of links, many of which point to compromised WordPress sites hosting other PDF files. This behavior is indicative of a link farm used to distribute malicious content or facilitate phishing attacks. ClamAV and ML classifiers also flagged this file as malicious, supporting the assessment of a phishing or trojan-like threat.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://realwebguys.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd11a32627---favibetitedodilixago.pdf In PDF document text
    • https://www.shopveriamici.com/wp-content/plugins/super-forms/uploads/php/files/9eahtjp56nijl2flm6s0k76ave/86162395659.pdfIn PDF document text
    • http://jaatkinson.com/userimages/menenowadajinozulexaven.pdfIn PDF document text
    • https://duext.com/wp-content/plugins/super-forms/uploads/php/files/95e933d38641889b3f20d6b326f61358/wunuwipobanilason.pdfIn PDF document text
    • http://ophirtonhotel.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160773d7df319f---14367242358.pdfIn PDF document text
    • https://dprkoreatour.com/uploads/files/52886640221.pdfIn PDF document text
    • https://electrabicycles.pl/app/webroot/uploads/file/16204586280832.pdfIn PDF document text
    • https://beautyyaurient.com/editor_upload/file/jadaku.pdfIn PDF document text
    • http://www.dadosefatos.net.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608cfb3c3dbe4---nakasuzusefipemamar.pdfIn PDF document text
    • http://ssaisarang.com/ckfinder/userfiles/files/miwovenumozimawadiwu.pdfIn PDF document text
    • https://amirep.com/wp-content/plugins/super-forms/uploads/php/files/0784d573c6c61b030ad5520836962c0e/99266147135.pdfIn PDF document text
    • http://agendatourvietnam.com/hinhanh/file/xilinoxej.pdfIn PDF document text
    • http://www.segurosfacility.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608d8d7b6fb6d---xarikatelebowazer.pdfIn PDF document text
    • https://www.pennlighting.com/wp-content/plugins/super-forms/uploads/php/files/2dbcb6a913a4182da1f902f517377943/23934743839.pdfIn PDF document text
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/a3480d8d523e7c7adf70431360be97ea/nerisabokunomojala.pdfIn PDF document text
    • http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/af0ad96b2035da8ea5bf2d5d1653e49f/zekexotulopumarajobilul.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608707e56ed1c---gagiroke.pdfIn PDF document text
    • https://airflow-skateboards.com/upload/file/rawexorelagomumuneke.pdfIn PDF document text
    • http://t-p-fortune.com/userfiles/file/7958176072.pdfIn PDF document text
    • https://an-professional.ru/img/files/file/dedepijozigixofosowa.pdfIn PDF document text
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c5f6c8648c7---jajekovoraruvotubo.pdfIn PDF document text
    • http://www.acefence.com/wp-content/plugins/formcraft/file-upload/server/content/files/16098fd8b5c186---wadatejejapefolivi.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/16087dabd43d1f---wudokixutezigodu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BkSY9tpko7c/uplcv?utm_term=ap+chemistry+2017+free+response+answersPDF 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_off0000c7c6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7C6 16920 bytes
SHA-256: 1b745a7bfb59ca466fba3ab4082c8cb24db071aeac7a2f308601789114b6ec3f
font_01_sfnt_off0000f3ce.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3CE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010be5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BE5 11224 bytes
SHA-256: c7e3909e1a0f3e9ec0ca3f8d00c8cc78165ddc047fcecd5f3e6708c40b84754e