Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b8729e04031bd44…

MALICIOUS

PDF

82.3 KB Created: 2021-07-19 22:29:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: 9b6012b0f59967c453b0155f9674443e SHA-1: 5fd899062bba3ba35e62ab915de520264160d1c2 SHA-256: 4b8729e04031bd448c58d3d6412675201fb6c315b2d1f6204a753295990e8613
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS upload directories or disposable hosting, suggesting an attempt to redirect users to malicious sites. The presence of multiple PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

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://bscartridge.com/pic/xadanawaxo.pdf In PDF document text
    • http://sl-light.ru/design/img/upload/file/79463464131.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16071827ecad18---xelewunenuwepogamolu.pdfIn PDF document text
    • http://whatdwellswithin.com/file/57624179430.pdfIn PDF document text
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091eeb7f1c2e---datakosujisoruzel.pdfIn PDF document text
    • https://charteriraq.ir/basefile/charteriraqir/files/53174425358.pdfIn PDF document text
    • http://amindoost.ir/images/upload/files/bepej.pdfIn PDF document text
    • http://itaindustrial.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a517538be16---lutezulijasegot.pdfIn PDF document text
    • http://ehomerealestate.org/images/file/50742675020.pdfIn PDF document text
    • http://sochi-polyana.com/ckfinder/userfiles/files/10001721246.pdfIn PDF document text
    • http://tikatalog.sk/_files/file/kuguwojejuwejev.pdfIn PDF document text
    • http://czytamzezrozumieniem.pl/userfiles/file/38457159617.pdfIn PDF document text
    • https://cullinanconstruction.com/wp-content/plugins/super-forms/uploads/php/files/hgdskmb1cu7o4lrjig257hus73/39123323572.pdfIn PDF document text
    • http://austria-ex.com/images/blog//file/67554682704.pdfIn PDF document text
    • https://sieuthimayphat.com/ckfinder/userfiles/files/duzulekix.pdfIn PDF document text
    • https://nanyangtextile.com/userfiles/file/12221313089.pdfIn PDF document text
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/75f96a0f75538b2e11401b89e54e9628/fubasetejom.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/xilawozijuponifurubebarow.pdfIn PDF document text
    • http://tebsc.com/clients/84181/File/narakaxipibupotugu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=ex+of+adverbPDF 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_off0000e213.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE213 16964 bytes
SHA-256: 67e424d88e83a5ffa4debcc032c6684e22350232a27f8f15a9a7751b6d77d75d
font_01_sfnt_off00010e10.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E10 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012627.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12627 10132 bytes
SHA-256: 3a791086ca7c4e9e40157b89c27341c0c3cb5fc5f7581122e8d40290a47c57f7