Malicious PDF — malware analysis report

Static analysis result for SHA-256 52b4be648f2e0b50…

MALICIOUS

PDF

73.0 KB Created: 2021-06-14 09:42:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: f01dd02cc064010b65389f5a838f39da SHA-1: 5bd36ca9fa36229718cf34476b2c2ceef99941e7 SHA-256: 52b4be648f2e0b50cca1751a609cf8ff18debb60955f1d85b9ed36fa816d3dd3
156 Risk Score

Malware Insights

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

The PDF document contains numerous links pointing to external websites, many of which are hosted on compromised CMS platforms or disposable hosting, suggesting a link farm designed to distribute malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution. The embedded URLs and the nature of the heuristics point towards an attempt to trick users into downloading further stages of malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://synerhu.ru/uplcv?utm_term=3d+animated+ppt+template+free+download PDF link annotation
    • https://wholisticvibrations.com/wp-content/plugins/super-forms/uploads/php/files/845ae79cbcbc888b1c047c857955b392/99364941593.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ffd2dbe98d---sajesuboweponexuk.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/f49757f377a0579171c3d87efa957fcd/vumowuwiziv.pdfIn PDF document text
    • https://wamsconference.com/wp-content/plugins/super-forms/uploads/php/files/b7c592410753c85194fa97e1073af0bb/kinowupejuvipediduna.pdfIn PDF document text
    • https://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160705bd9d3867---85068300090.pdfIn PDF document text
    • https://www.advids.co/wp-content/plugins/formcraft/file-upload/server/content/files/16086afc06c6f3---19620197189.pdfIn PDF document text
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/e1373325bf6cfb9a155b5beb61af7a6e/kolorejiwomesuludizives.pdfIn PDF document text
    • https://laneopx.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9269955b15---zekekevet.pdfIn PDF document text
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16090db9b19f51---gedozanexepezetej.pdfIn PDF document text
    • http://xn--90ad5ackt1d.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/7c6f7709af4f94758e469281ea1d8ad7/rarebaj.pdfIn PDF document text
    • http://4grd.com/cmsimages/file/zolozutom.pdfIn PDF document text
    • http://cosmic-kino.ru/sadm_files/jagekuta.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607db1dc11f86---26423661679.pdfIn PDF document text
    • https://vietfun.com.vn/wp-content/plugins/super-forms/uploads/php/files/4gd795o4etimuglra6qpjk0hb4/74416178993.pdfIn PDF document text
    • https://www.audifonosdoshoydos.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b50d901238---siwinuzebiv.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b595f85b431---xiwijitano.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e16a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE16A 5172 bytes
SHA-256: c4bd553a75dc669d3473011a277562dff495dc63dd71dc9f167f1539db92094d
font_01_sfnt_off0000f2f9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2F9 10504 bytes
SHA-256: ece3d617bd5d904b71ca2b1cdba4563303cc20f1a877ac640d9a56e1d157f11c