Malicious PDF — malware analysis report

Static analysis result for SHA-256 1833ca4280d8d026…

MALICIOUS

PDF

82.9 KB Created: 2021-09-03 10:09:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 6b4804daa37f3435b4d362b404fdf311 SHA-1: 58ca97e7387e015461604a617d3f342c1bd2029b SHA-256: 1833ca4280d8d026969b33f200edd7bf31d6a1b57434fefd8a73143492a2acc0
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and numerous external URIs, many of which point to compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' strongly indicate a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection further support its malicious nature, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://itracmediav5.com/ckfinder/userfiles/files/walapogimudisisuki.pdf In PDF document text
    • http://ats-dz.com/userfiles/file/fiwekuf.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/57393139329.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/vasejimaxeganom.pdfIn PDF document text
    • http://artgraf24.pl/userfiles/file/bowevesune.pdfIn PDF document text
    • http://www.jacenter.org/js/ckfinder/userfiles/files/xuwoxewave.pdfIn PDF document text
    • https://hsiaoying.com/userfiles/file/45074336029.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/6c7ded804ecc1b7fa0772c839d545bdb/47213630225.pdfIn PDF document text
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160bfc354567b4---99317531356.pdfIn PDF document text
    • http://davcpundri.com/css/file/gerajuzogojinokiw.pdfIn PDF document text
    • http://manufim.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160bc2d2966299---44540075784.pdfIn PDF document text
    • http://doktor-okonski.pl/uploadimg/file/weduba.pdfIn PDF document text
    • http://www.kidnuri.com/wp-content/plugins/formcraft/file-upload/server/content/files/16088afd60aa9c---70259301230.pdfIn PDF document text
    • https://www.la-providence-ehpad.fr/ckfinder/userfiles/files/85194779195.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e961b2a3ed---38646287770.pdfIn PDF document text
    • https://www.kiteschule-kiel.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608e937a0e269---88712605644.pdfIn PDF document text
    • https://upbfassadenbau.com/upload/file/lawewobugufeti.pdfIn PDF document text
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/0b4fd0ef7447700f98deaf1209a071f1/xagafineziwusomom.pdfIn PDF document text
    • http://ontheedgeofnow.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a002968b84---97198294716.pdfIn PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608cb288e4c65---23571892821.pdfIn PDF document text
    • http://alvasari.com/wp-content/plugins/formcraft/file-upload/server/content/files/160715ae6b6971---13523660961.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ce9313ca70a---nemezasunonapami.pdfIn PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/torufelogumimenoke.pdfIn PDF document text
    • http://01host.ru/userfiles/files/27261314701.pdfIn PDF document text
    • http://cuborh.com/natelinhanew/js/ckfinder/userfiles/files/31374188704.pdfIn PDF document text
    • https://xlux.vn/wp-content/plugins/super-forms/uploads/php/files/vvkdm65eveore9gdla44mu0lhm/gepub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=adding+decimals+word+problems+pdfPDF 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_off0000dfe7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDFE7 11072 bytes
SHA-256: e3f0fbaeb6cdda37b2010166730fa28db75cbb07bfa8c112e0f58ff5f4c84666
font_01_sfnt_off0000f946.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF946 17380 bytes
SHA-256: adefd7e5b7fb00154851fc702e3ebe17361fda28f9a190f807ebbf48a5e51183
font_02_sfnt_off000125da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x125DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1