Malicious PDF — malware analysis report

Static analysis result for SHA-256 23fd016b849c1698…

MALICIOUS

PDF

74.4 KB Created: 2021-06-17 22:17:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 43400e828e36d3a3b530ce4296515e6c SHA-1: b761ba565ed308389260ccf9230764a92e9e11aa SHA-256: 23fd016b849c16987c4571703ce01f56a326197876069e27af7d4ccc50cae1e6
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to compromised WordPress sites, designed to trick users into downloading further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the PDF structure and URLs suggest a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://adoriantarla.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f72e38e7f---19933143194.pdf In PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607b7e2f3522a---81856901420.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c4ff7c45cd---kumoxuwilizoderonajokab.pdfIn PDF document text
    • http://lookupagency.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607e33c4b61eb---zamanegegofiresugulefagov.pdfIn PDF document text
    • https://cashmeredreams.com/wp-content/plugins/super-forms/uploads/php/files/a1bc08c7eeb324aebd65a23091e8b3db/21407577927.pdfIn PDF document text
    • http://wsm.hk/images/uploadfiles/file/wonewatibuzasajuka.pdfIn PDF document text
    • http://przychodnia-felinskiego.pl/uploads/editor/file/bosowarimuba.pdfIn PDF document text
    • http://allseasonsart.com/uploads/fck_uploads/file/1507359472.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/orqvqa1or06fb745muqr82u0es/86705238912.pdfIn PDF document text
    • http://terapeutickemasaze.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609d4cc952ab9---kileka.pdfIn PDF document text
    • https://www.pietri-automobiles.com/wp-content/plugins/super-forms/uploads/php/files/0ppc2kf20khedm8aq260bqn231/pivixezewokadadinefowu.pdfIn PDF document text
    • http://studiodabo.eu/userfiles/files/7977380708.pdfIn PDF document text
    • https://sinhadventure.com/uploads/file/23200278131.pdfIn PDF document text
    • http://seednseed.com/admin/fckfiles/file/810171275.pdfIn PDF document text
    • https://vate-tire.ru/wp-content/plugins/super-forms/uploads/php/files/4140786da2d3b88939e4fe540c086663/gafiwepefevozapovix.pdfIn PDF document text
    • https://lensprovn.com/ckfinder/userfiles/files/39281147153.pdfIn PDF document text
    • http://jeugdopdewetenschapsagenda.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16088e1fe5a51e---rizagisofuwukivobexuluvup.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=telugu+love+failure+songs+download+mp3PDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e422.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE422 5628 bytes
SHA-256: a76f570dd132692a752f8586842a223080fba9b3db7e859e997c683221b5d936
font_01_sfnt_off0000f74e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF74E 10768 bytes
SHA-256: a1c434aa9332c3391ed3c3f440ba0ad591f17a5179b329628fb15cd409dc702a