Malicious PDF — malware analysis report

Static analysis result for SHA-256 de5dcf5fbeb68507…

MALICIOUS

PDF

72.2 KB Created: 2021-10-01 19:01:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 0feffd1825af86b1a4dcfe72c7c24f89 SHA-1: f32c0fdf94d671327fb54feff9e74dbfd7eb6aa2 SHA-256: de5dcf5fbeb68507cb8ced65b749fa3986ab0cafa1e10ca02fa379aed1988a83
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution T1059.007 JavaScript

The PDF file contains a large number of links pointing to various websites, many of which are hosted on compromised CMS platforms or disposable domains. The ML classifier strongly indicated maliciousness, and the link farm structure suggests an attempt to lure users to potentially malicious sites for phishing or further exploitation. No scripts were extracted, but the PDF structure and embedded URLs are indicative of a malicious campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://smidgel.ru/uplcv?utm_term=imo+imo+call PDF link annotation
    • https://srilangkapools.com/contents/files/tumopagufagisid.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/pawez.pdfIn PDF document text
    • http://klick-tipp.at/ckfinder/userfiles/publics/files/54533402452.pdfIn PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161441b1011ad8---59274117694.pdfIn PDF document text
    • http://dongsimkindergarten.com/upload/files/19481225529.pdfIn PDF document text
    • https://ag-concept.ru/wp-content/plugins/super-forms/uploads/php/files/8b0893b1a8c75b8af929a8aeb223f2e1/kidusirafeluwinexeforole.pdfIn PDF document text
    • http://levakov132.ru/userfiles/file/tunipibip.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/16148fa6460362---28717108479.pdfIn PDF document text
    • https://equalland.com/uploads/File/95313600359.pdfIn PDF document text
    • https://heuresromantiques.com/upload/files/49362163717.pdfIn PDF document text
    • http://a2itsolutions.com/chop/multimedia/userfiles/file/87224121976.pdfIn PDF document text
    • http://geose.ru/userfiles/file/bekerofuwulin.pdfIn PDF document text
    • http://xn--12cbg9dihj7egda2g6a7dceb1d2cp4nvgf4f.com/datas/files/siminudenemoj.pdfIn PDF document text
    • http://kalkulacka-hypo.cz/userfiles/files/gesokixapesuzawu.pdfIn PDF document text
    • https://tuinvandecruys.be/file/10519448492.pdfIn PDF document text
    • http://samocvet.org/foto/ck/files/sebaramuparul.pdfIn PDF document text
    • http://newshop.jp/archive/file/16045165103.pdfIn PDF document text
    • http://cameragiaminh.com/upload/files/munagifaposupega.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/7hoff2ho87d7rucjqlacsc5tl6/lozifijola.pdfIn PDF document text
    • http://vcelari.naceradec.cz/includes/ckfinder/userfiles/files/gabote.pdfIn PDF document text
    • https://golf-tout-terrain.com/publish/page/file/97282996749.pdfIn PDF document text
    • http://kjphotocon.org/data/userfiles/files/juxet.pdfIn PDF document text
    • http://brilsports.ro/userfiles/file///36716393304.pdfIn PDF document text
    • http://www.brickchamber.com/ckfinder/userfiles/files/46145444200.pdfIn PDF document text
    • http://miryangpension.com/FileData/ckfinder/files/20210901_0BA12E3D225AEDAA.pdfIn PDF document text
    • 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_off0000b721.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB721 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000cf37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF37 9740 bytes
SHA-256: c1657234c35cf102f448a2f1aa4c8df2027b75eadac7e4cada8db681ce144c78
font_02_sfnt_off0000e469.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE469 18504 bytes
SHA-256: e53389d514cf0b713fde1d3aa7c28f6adfa5c80b8e3e07843fd37d46ae31ab9f