Malicious PDF — malware analysis report

Static analysis result for SHA-256 fd5168c32fd2a2ff…

MALICIOUS

PDF

72.8 KB Created: 2021-06-23 13:14:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-24
MD5: 7e0fece1699efca2a77f7a2ebc439610 SHA-1: 25f0a62210c3151609a1e75c6573169e832dc54f SHA-256: fd5168c32fd2a2ffecea9c206d0302361778a0e7457f1a2776bec81ef8f1a54a
156 Risk Score

Malware Insights

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

The file is identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable hosting, suggesting a tactic to distribute malicious content or phishing pages. The presence of external URIs and the overall structure strongly suggest it's part of a phishing or SEO poisoning campaign.

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://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/urdnl7il40ksjahlr8i585dii9/padak.pdf In PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/5b8013323613156069b9f5e3dc7db7c1/89559880563.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/160831885c2f8e---60623719022.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607fc49773d86---51497661107.pdfIn PDF document text
    • http://mirrorgallery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092b360e761f---towodod.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c42d9bc8197---zubuxotemunepifat.pdfIn PDF document text
    • http://reszke.pl/fckeditor/editor/filemanager/connectors/php/file/52693970692.pdfIn PDF document text
    • https://www.vigo.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16075dce88358b---wivemunilu.pdfIn PDF document text
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ad5e0204f8---37812875449.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083d6ee3fedb---wumagomuwigu.pdfIn PDF document text
    • http://taiwanglassgroup.cn/userfiles/file/42936476587.pdfIn PDF document text
    • http://eksan-ltd.com/userfiles/file/68907623027.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160cb0483520b6---vizupepegogonolo.pdfIn PDF document text
    • http://www.contal-farmer.com/uploads/files/pudisole.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d2d1682b00---fasetefugideluvagagamirar.pdfIn PDF document text
    • http://transinfosoft.com/userfiles/file/43636084082.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/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=class+4th+maths+worksheet+pdfPDF 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_off0000dd6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD6D 5428 bytes
SHA-256: b75e1602b256d87d5e21d82ed09ab53e5ca1cf9ce272b5a94239ed47b2655868
font_01_sfnt_off0000efcb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEFCB 11292 bytes
SHA-256: d59b59c8c4715281c1ae9eeefe9da13b9e60e237b0b188c767308282a63f55be