Malicious PDF — malware analysis report

Static analysis result for SHA-256 eca5bac502711d6e…

MALICIOUS

PDF

81.3 KB Created: 2021-06-05 20:41:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: 18007119df430bf3d10126053f126bd2 SHA-1: 39b7a34c21863f1c583a6cd702d64e228b402290 SHA-256: eca5bac502711d6ed80086998863c541d1890a5991e9eaa6df447f76748844a2
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised WordPress installations or disposable domains, suggesting a link farm or phishing campaign. The ML classifier and ClamAV detection strongly indicate malicious intent. The document body, though heavily obfuscated, appears to be a lure related to educational content to disguise the malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://allytemp.ru/uplcv?utm_term=how+to+develop+critical+thinking+skills+in+college+students PDF link annotation
    • https://www.alarisusallc.com/wp-content/plugins/super-forms/uploads/php/files/9d7e6b25d49520f8b9a5b01bcdebf3d3/fanexepirinopagev.pdfIn PDF document text
    • https://www.ideaklinik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c461f88b82---30599166584.pdfIn PDF document text
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/853a413a3294f849f27ad3f01b722aa3/13521791542.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607456441db1d---82646277409.pdfIn PDF document text
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a5e671faf1---87262571259.pdfIn PDF document text
    • http://theopenhouseclub.com/wp-content/plugins/super-forms/uploads/php/files/c2324b819cc3973903f0364a9d5ae616/52329114465.pdfIn PDF document text
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/5b89t0vnfvij2gel1tdaoghhsi/vunateduremar.pdfIn PDF document text
    • http://france-ex.com/images/blog//file/nesojafevubure.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/59011c6360f6e0989bb8b9f5ef42b0c9/ginezuzugowuzaxumebagexi.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/c9c8ifpvt48gm8hehjqqvpgfp3/55324960928.pdfIn PDF document text
    • http://ash-graphy.com/userfiles/file/96179948520.pdfIn PDF document text
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/ba186565df09ef8f596081dc2239fdd8/45851236158.pdfIn PDF document text
    • http://www.ponderosafestival.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095d738ae006---mupogem.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/4n895tpa5dk2cbqrf9g9jclqtr/wagaxaw.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160b778068134d---xeperagezokepogasorilawi.pdfIn PDF document text
    • https://matskaren.se/anvandarbilder/203/files/fifapesinexu.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_off0000fe94.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE94 5512 bytes
SHA-256: 3905e9e764609d846d6d805c06a330c32d4ab2a4516cdc2dbc92c0ef0a37f1be
font_01_sfnt_off00011163.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11163 10736 bytes
SHA-256: 037eed488cade0682f16c2a74026836fcb5e31bdcc6e2f999a833f166496d260