Malicious PDF — malware analysis report

Static analysis result for SHA-256 538e792cfff49891…

MALICIOUS

PDF

73.9 KB Created: 2021-09-12 01:24:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d7c53b8a85011407e6a29eb9211599d8 SHA-1: 90da1adb26cfc863f25f63124c303945c4edaccc SHA-256: 538e792cfff49891820a9c379f1e04e395e61dd7a6e072cf8c01e72edc3ccfa8
180 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file contains embedded JavaScript and a link farm pointing to multiple external URLs, indicating a malicious intent to redirect users. The heuristics suggest it's a phishing or malware distribution lure, likely delivered as a spearphishing attachment. The ML classifier and ClamAV detection strongly support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 9

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://infrive.ru/uplcv?utm_term=my+hero+academia+heroes+rising+full+movie+eng+dub
    • http://perechen-izdaniy.ru/js/ckfinder/userfiles/files/vokeriwomigenawifu.pdf
    • https://echipamente-scule.ro/userfiles/file/nifibe.pdf
    • http://www.jesuseslaroca.org/wp-content/plugins/formcraft/file-upload/server/content/files/1613c7b0d84e23---limusozenumorawulawiwukeb.pdf
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/49a1702b7fc1895d8a3da506261b473c/26410331423.pdf
    • http://fantalife.nl/userfiles/file/4380235329.pdf
    • http://tzoetemondje.be/uploads/files/gamelepegexakila.pdf
    • http://eros-arena.name/eros/userfiles/file/64512980937.pdf
    • http://somsit.com/ckfinder/userfiles/files/56873272524.pdf
    • http://chenruichem.com/upload/files/45210725854.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b0d2ff0c76---nivumobubutijovin.pdf
    • http://portaldeaquidauana.com.br/ckfinder/userfiles/files/43596070472.pdf
    • http://weiddy.com/uploads/files/202109091527145262.pdf
    • http://provia-events.de/pics/fotos/1/file/27829011640.pdf
    • https://nstoplana.rs/ckfinder/userfiles/files/58898658743.pdf
    • http://esllearningbydesign.com/app/webroot/files/file/24088355903.pdf
    • https://nsstore.mx/ckeditor/ckfinder/archivossubidos/files/77533624188.pdf
    • http://bodegaadrover.com/userfiles/imagenes/27413751356.pdf
    • https://himalayanespresso.com/espresso_ckfinder/userfiles/files/82633551766.pdf
    • http://ytlcases.com/userfiles/file/26645887646.pdf
    • https://home18.ru/wp-content/plugins/super-forms/uploads/php/files/8ec6817870c291d1c5ae4b4a99eb802d/mumuxeneril.pdf
    • https://mercerapparelss.com/userfiles/files/12167259808.pdf
    • https://pre-www.bridge-college.com/uploaded/ckeditor/files/7714109442.pdf
    • https://colegiumaniucarei.ro/ckfinder/userfiles/files/52093244655.pdf
    • http://as-eng.biz/userfiles/file/99519632661.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_off0000b89d.bin
b43d92cf50ea0f59b8a79061b2e404116be3fc9efedd4a77e244e6a22217c6df
pdf-font-stream PDF embedded font (sfnt) at offset 0xB89D 11236 bytes
font_01_sfnt_off0000d296.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD296 16792 bytes
font_02_sfnt_off0000eaa8.bin
608f93468be760e7a3295a3240d965cbec781dfd34cb1635968e50a5c134ce8a
pdf-font-stream PDF embedded font (sfnt) at offset 0xEAA8 17504 bytes