Malicious PDF — malware analysis report

Static analysis result for SHA-256 84799c6055387b9b…

MALICIOUS

PDF

75.0 KB Created: 2021-09-18 06:17:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 7f0596bbb54abc3b222f7e65e68dfa69 SHA-1: d706e045464e96f16b8d09e06ca62fe9acf0f698 SHA-256: 84799c6055387b9b1b9da1d6065cba31537b780f0a87bbac831505bdc8d4cc76
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as Pdf.Phishing.Trojan and an ML classifier indicated a high probability of maliciousness. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS uploads. The presence of external URIs and link farm characteristics suggests an attempt to redirect users to malicious or phishing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://edu-soft.ru/site/htmlimages/file/24370164802.pdf In PDF document text
    • http://watthaistuttgart.de/userfiles/file/64436403211.pdfIn PDF document text
    • https://stvorki.ru/files/file/87339291811.pdfIn PDF document text
    • https://flyags.com/editorResources/file///18631242305.pdfIn PDF document text
    • http://dyglas.com/userData/board/file/nosofadedipopelupire.pdfIn PDF document text
    • https://millvalley.com/wysiwygfiles/file/41744637695.pdfIn PDF document text
    • http://lorofilmes.com/Uploads/ckfinder/userfiles/files/lasufenovulenewajikavosu.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16142c9c6c2eaa---41746012095.pdfIn PDF document text
    • http://de.ruben.pl/ckfinder/userfiles/files/nikidelazasenisoxupav.pdfIn PDF document text
    • http://vangphutai.com/images/uploads/files/dudupiwefirixo.pdfIn PDF document text
    • http://apluskleaning.com/admin/images/file/58766272532.pdfIn PDF document text
    • http://tugrabilgisayar.net/resimler/files/redojagedojisumapowabelos.pdfIn PDF document text
    • http://basaritarim.net/admin/editor_resim/file/jamiserij.pdfIn PDF document text
    • https://sumangold.net.vn/wp-content/plugins/super-forms/uploads/php/files/2vakamut70joqgh63ldftm6arb/29766689387.pdfIn PDF document text
    • http://ccsctda.com/ckfinder/userfiles/files/20210912_054829.pdfIn PDF document text
    • http://esrafisek.com/images_upload/files/miwavalego.pdfIn PDF document text
    • http://cnokorea.com/userfiles/file/ropuvebekexakitibewed.pdfIn PDF document text
    • https://vaitinhdien.com/app/webroot/upload/files/nivelapisiwowusexejubaju.pdfIn PDF document text
    • https://bepcongnghiepphuchung.vn/userfiles/file/74443475758.pdfIn PDF document text
    • http://ritadas.in/userfiles/file/sowivunalov.pdfIn PDF document text
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613fda051b5d9---66950237878.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161445315e18da---namesexowidefal.pdfIn PDF document text
    • https://texasbordervolunteers.org/userfiles/file/86136481076.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/LPIa9PGmDLg/uplcv?utm_term=omegle+chat+internationalPDF 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_off0000c122.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC122 10532 bytes
SHA-256: cec9a383926f761c73d429126735ca02d3e68c3797f4447b65ff4a40c982a8d9
font_01_sfnt_off0000d8ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8ED 17724 bytes
SHA-256: 355b8f29d0f822b66ffd8ee3b5177e652dabd63030d0ec68e644b42d8d1b17b4
font_02_sfnt_off00010678.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10678 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1