Malicious PDF — malware analysis report

Static analysis result for SHA-256 d51990599c6a0f4f…

MALICIOUS

PDF

166.0 KB Created: 2021-07-30 06:32:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 1b29afa49072947043cf59f311b017f3 SHA-1: b70dc37c12e45a8fe92d5c0f0262d679baa423c2 SHA-256: d51990599c6a0f4ffc9d1628cb8b07f2a08c16830ae82f0147468f2408d724ef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The PDF contains numerous links to external websites, many hosted on compromised CMS platforms or disposable domains, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the nature of the PDF and its embedded links strongly suggests it is used as a lure, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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://pistant.ru/uplcv?utm_term=why+did+the+vikings+invade+england+ks2 PDF link annotation
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/ac49dadaafab278a96b1a8d9ec7564b1/muwusevuvoxejanumuboko.pdfIn PDF document text
    • https://trimix.bg/UserFiles/File/6008271312.pdfIn PDF document text
    • https://marljivo.hr/userfiles/file/7744344023.pdfIn PDF document text
    • http://elcampoeco.org/FCKeditor/file/zotulevaxezirijo.pdfIn PDF document text
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072d8374f397---27031680010.pdfIn PDF document text
    • http://aldo-ins.com/userfiles/file/pibolozepinujipigedoregip.pdfIn PDF document text
    • https://novahealthclinic.ca/userfiles/file/33196851992.pdfIn PDF document text
    • https://myhoorayhealth.com/wp-content/plugins/super-forms/uploads/php/files/bkj4jh43nohe90a4dq3v8nioc6/lepavepefosewosevolu.pdfIn PDF document text
    • http://ampletrekking.com/userfiles/file/68293529749.pdfIn PDF document text
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cd3f11da2a---7611043317.pdfIn PDF document text
    • http://21cedu.com/pds/userfiles/files/jagudovapise.pdfIn PDF document text
    • http://bestapp4u.com/admin/uploadedfiles/file/64168339516.pdfIn PDF document text
    • http://bagiez.de/userfiles/file/bowitegote.pdfIn PDF document text
    • http://xn--aknmedical-yub.com/uploads/file/tinovunamuxanoxo.pdfIn PDF document text
    • http://vasvaripalmuzeum.hu/upload/file/95593584945.pdfIn PDF document text
    • http://www.siscbolivia.com/admin/uploaded/fck/file/38799505190.pdfIn PDF document text
    • https://dhcom.vn/userfiles/file/70692216826.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160abf8b6becab---pawovobotajobug.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/160743cf9f1d10---sobafepaxoxuvid.pdfIn PDF document text
    • https://binarbaidequipment.com/public_html/userfiles/file/98595503006.pdfIn PDF document text
    • http://ash-graphy.com/userfiles/file/10449590989.pdfIn PDF document text
    • http://accapierre.it/userfiles/files/temukugogukavumifepa.pdfIn PDF document text
    • http://stuarteisbrucklaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/56277681573.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_off00021f1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x21F1F 23704 bytes
SHA-256: 0e12ba9a5361c0738a6e7519f2b8a21dbe4e810dc88fab8156a295fd9fb0767f
font_01_sfnt_off00025973.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x25973 10692 bytes
SHA-256: d19b6f82899da93f1f91cb34606fccf112b1984dd75398e64ad6f6f853f5a7d7
font_02_sfnt_off000271c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x271C5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1