Malicious PDF — malware analysis report

Static analysis result for SHA-256 3b71a419ea3e8e87…

MALICIOUS

PDF

84.5 KB Created: 2021-06-26 16:41:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 732c6f4a40af7c4f7cedcc6b1246b2e5 SHA-1: b8400832117afbe8c5a6d4babe4f97871af5e0ee SHA-256: 3b71a419ea3e8e87637f6cd04bb94bd4d6a3574eea25489d83db0da8dd7df2e4
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or utilize disposable hosting, indicating a link farm for phishing or malware distribution. The ML classifier strongly flagged this PDF as malicious. While no scripts were explicitly extracted, the presence of embedded URLs and the nature of the heuristics suggest the document is designed to redirect users to malicious content, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 5

  • 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://crysiq.ru/uplcv?utm_term=effectiveness+of+training+and+development+project+report+for+mba+pdf
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1608124dbe20ff---supesopug.pdf
    • http://hkalc.com/userfiles/ledewigesejirazekudodofo.pdf
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607be06d1aa03---88583864625.pdf
    • http://walker-doss.com/clients/4/45/450b4a4af5ff3f13851793278d9c7ef8/File/libifudirowin.pdf
    • https://paidionresearch.com/userfiles/files/xudagowule.pdf
    • https://digireg.se/upload/mevoveginogizagimokud.pdf
    • https://holocaustresearch.pl/nowy/photo/file/narolujer.pdf
    • http://toeicspeaking.net/_UploadFile/Images/file/53909703276.pdf
    • http://canxetaidientu.com/images/file/15889316689.pdf
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/16087c2b6f2f20---ponilunaleruli.pdf
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bed43a58148---81141495267.pdf
    • http://orgue-chantepie.info/FCKeditor/upload/file/54916930255.pdf
    • https://formapolis.it/wp-content/plugins/super-forms/uploads/php/files/0ba3b7a96200469844095165add49fed/pakagojizegofe.pdf
    • https://investainternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085796bd1943---35479073486.pdf
    • https://amagi.la/wp-content/plugins/formcraft/file-upload/server/content/files/1606f920062f7c---53286586257.pdf
    • https://thehamptonsbloomington.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607dec1cef48b---85210654228.pdf
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160a365807d648---45244027970.pdf
    • http://alexlunacoach.com/img/editor/file/60356230163.pdf
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607d9c79838dd---75344903116.pdf
    • https://www.napariverinn.com/wp-content/plugins/super-forms/uploads/php/files/5c92340f02a6a1bda4678c0874ea80f7/86552773050.pdf
    • http://mintaialuminum.com/d/files/wifafuzasatapoveri.pdf
    • http://snap-drone.com/userfiles/file/xupozarabudomawuj.pdf
    • https://oneremote.ru/wp-content/plugins/super-forms/uploads/php/files/65e8d10d3a60d2af8c7661d71d7dbbec/27795159060.pdf
    • https://cabsfromheathrow.com/userfiles/file/narilejarutajizorufibib.pdf
    • https://laser-arena.ch/wp-content/plugins/formcraft/file-upload/server/content/files/16083f7e804b3b---66328342409.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e78e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE78E 16792 bytes
font_01_sfnt_off0000ffa0.bin
3bc2d5647b769e834f1c389bf8a6bcdca644e4180771f75b73be3fa5023b9721
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFA0 16508 bytes
font_02_sfnt_off000129bf.bin
874911811dbf64c96f896a9e20072df481be7b583130efc5718b4c0e7bbcf876
pdf-font-stream PDF embedded font (sfnt) at offset 0x129BF 11280 bytes