Malicious PDF — malware analysis report

Static analysis result for SHA-256 588d1fbb68e3d657…

MALICIOUS

PDF

76.9 KB Created: 2021-09-18 02:36:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: c956529a3022a49062832ca360a1f883 SHA-1: 9fce241a8a902e903fda8c2fd92533a9c92b677c SHA-256: 588d1fbb68e3d6577febd586bf0f3525ae4f72592878357dccb4cd95d11565cd
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS upload storage or are part of a link farm on disposable hosting, suggesting an attempt to redirect users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues to its intent beyond the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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 http://uitetenindex.nl/images/uploads/fifatazapi.pdf In PDF document text
    • http://crystal-lamp.ru/uploads/files/dugejopujudukerenow.pdfIn PDF document text
    • https://gogift-it.com/userfiles/files/jemitowigizenituni.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/3vmaghqevtkvc6kvqrv5m97vhs/54595697040.pdfIn PDF document text
    • https://artofsurfing.com/preview/ckfinder/userfiles/files/parisasujubuposisugo.pdfIn PDF document text
    • https://alkirbilaw.com/userfiles/files/zadusibupok.pdfIn PDF document text
    • http://birons.net/wp-content/plugins/super-forms/uploads/php/files/ee7dec6dfd5dee5518942cee20bfae01/4255184666.pdfIn PDF document text
    • http://bezpiecznamlodosc.org/files/file/36239646319.pdfIn PDF document text
    • https://luckyfood.itweald.com/uploads/files/613ff1dd4faca.pdfIn PDF document text
    • http://savitaco.com/uploads/images/files/rovikuxu.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16144424110526---69132764319.pdfIn PDF document text
    • http://www.belladermeestetica.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613d3509ad5b9---87554425589.pdfIn PDF document text
    • http://auksozvynas.lt/userfiles/file/72795329558.pdfIn PDF document text
    • http://lingeriedediva.com/UploadFile/file/2021090714150873499.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613662261bc87---kegezozurani.pdfIn PDF document text
    • https://www.edm-medical.net/ckfinder/userfiles/files/rimaduxixobuno.pdfIn PDF document text
    • https://zifu-tech.com/app/webroot/userfiles/files/1758626947.pdfIn PDF document text
    • https://sunridgecorp.com/uploads/files/202109132237599821.pdfIn PDF document text
    • http://thuocnam.xyz/images/files/82216102522.pdfIn PDF document text
    • http://studiophotosfashion.it/userfiles/files/26516652109.pdfIn PDF document text
    • http://ahknchem.com/upload/files/butamefaragumuma.pdfIn PDF document text
    • http://lavalnerina.com/userfiles/file/38248886498.pdfIn PDF document text
    • http://audidalys.lt/ckfinder/userfiles/files/tidididajodujumos.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/PmAiG5ZyT-k/uplcv?utm_term=rick+and+morty+episode+3+season+5+watch+onlinePDF 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_off0000c516.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC516 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000dd2d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD2D 11424 bytes
SHA-256: 326df132c8fba84cdeb0a15e6c83e0f99ffcdc2225de23b704c88ddd9b8bb7b0
font_02_sfnt_off0000f80f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF80F 17848 bytes
SHA-256: 5d71f5ebf6d2d8eb5f8c007e5cfcfec676dc421abd741773705462ae4ed9dc5d