Malicious PDF — malware analysis report

Static analysis result for SHA-256 17fe638b12bad423…

MALICIOUS

PDF

103.1 KB Created: 2021-06-03 14:17:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: 958c89bbee97a153b84e3cdd701e008a SHA-1: c99c8f8468b72d590ef148850d92b7c97c167752 SHA-256: 17fe638b12bad42346b6aa8a1a08020edbab7cae1a028b6b4c0b7b0629c92c87
186 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a large number of external links, many pointing to disposable hosting, suggesting a link farm designed to distribute malicious content or phish users. The document body, though heavily garbled, contains text related to 'Aday retmen formlar1' which translates to 'Trainee teacher forms', aligning with the link farm's apparent theme. No scripts were extracted, but the PDF structure itself is indicative of malicious intent.

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
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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://jacksth.ru/123?utm_term=aday+%25C3%25B6%25C4%259Fretmen+formlar%25C4%25B1+%25C3%25B6rnek+kitap+listesi PDF link annotation
    • https://vilawamilufulob.weebly.com/uploads/1/3/6/0/136006615/3308154.pdfIn PDF document text
    • https://gugakelu.weebly.com/uploads/1/3/5/9/135965899/5385650.pdfIn PDF document text
    • https://dedidolijara.weebly.com/uploads/1/3/4/6/134666782/veverujikug.pdfIn PDF document text
    • https://fibexijenoka.weebly.com/uploads/1/3/2/6/132680926/sebusib-favube-vosow-girojamob.pdfIn PDF document text
    • https://bewuzitavunu.weebly.com/uploads/1/3/4/3/134349104/bazuwesoza.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/4b1a25d5-8273-4f84-ac2f-67a485c33f6d/20876707190.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/eba86547-2713-4e88-8cf8-deab0e0f3788/poziniginerukutibop.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/d831cc39-9e16-41a9-aeff-5d0ce13c9bbc/how_to_draw_simple_flowers_step_by_step.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a3a02c88-6295-4e4b-93e9-05cec80c5ed1/dojidid.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/40ef2295-2e30-4f9e-b054-f4d2e08e0cfa/smart_bracelet_manual_dansk.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e4f1b52f-9d96-4f5f-ac70-a29041e82d73/washing_britax_advocate_car_seat_cover.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/129f95d8-f3a6-4652-9ec9-90a9aff53416/76769086849.pdfIn PDF document text
    • http://nosegawibaso.pbworks.com/w/file/fetch/144524652/zugupabaso.pdfIn PDF document text
    • http://puzavofan.pbworks.com/f/how_to_clear_versant_test.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/e1eddbe3-b39e-4710-8702-7047df991814/fapoxavomegini.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/8d9daa49-b5dd-4a6a-b861-8d639d38e799/92559173983.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/96e7fd60-2fe5-4d7b-a62c-dd1d1d1d1869/76225343935.pdfIn 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
    • 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_off00013b53.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B53 5740 bytes
SHA-256: 8a738af49af8173837c09ca2c22d4c4ff4f374dacfdd47224c67596b6eeae764
font_01_sfnt_off00014ea1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EA1 13264 bytes
SHA-256: 4a0c97dd6194940baa89c983c09207aa9bb7cf245b73555122660c65e47d02d9
font_02_sfnt_off00017745.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17745 16204 bytes
SHA-256: 541fa2b6826b0add99b7d5a173ef1e6a5567607b5192f75b810eb17d6a563501