Malicious PDF — malware analysis report

Static analysis result for SHA-256 39c2618b16b973df…

MALICIOUS

PDF

75.7 KB Created: 2021-05-29 23:57:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: fc1836eff2e1cc0b5a33022e4e6a814a SHA-1: 9ede69edaefd0273c1659765a6c04dcd8003b29a SHA-256: 39c2618b16b973dfad61256c6b5fedec4c96e43596f5170ec1c922102b07fa1f
186 Risk Score

Malware Insights

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

The PDF contains a large number of external links, many pointing to disposable domains, indicating a link farm or phishing attempt. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to redirect users to a malicious site for further exploitation or credential harvesting. No scripts were extracted, but the PDF structure itself is indicative of a malicious lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://fokemale.ru/strik?utm_term=a+tangled+web+oxford+bookworms+collection+pdf PDF link annotation
    • https://kimimidinom.weebly.com/uploads/1/3/1/4/131453749/milutelufunonugo.pdfIn PDF document text
    • https://pimimazeso.weebly.com/uploads/1/3/4/5/134523822/zibijesan-nijesopilagov.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4489717/normal_603678d285e1a.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4470679/normal_601eb662d9aa7.pdfIn PDF document text
    • https://mixorone.weebly.com/uploads/1/3/1/4/131438240/275e0da897f.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4488558/normal_6022497e39b1d.pdfIn PDF document text
    • https://binewetakug.weebly.com/uploads/1/3/5/3/135326509/gomila.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4370555/normal_605c02b4e3388.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4495551/normal_5ffac1b75d814.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4382193/normal_60403439d59d6.pdfIn PDF document text
    • https://static.s123-cdn-static.com/uploads/4447107/normal_60031f23b7c30.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4393041/normal_5fdaa9855d9a3.pdfIn PDF document text
    • https://faruroju.weebly.com/uploads/1/3/5/9/135986438/5177513.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://uploads.strikinglycdn.com/files/8f08d956-c7a8-446a-a0ae-b18d74122a0a/tedojivosupovupiwiz.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/367d885d-460b-42ae-b4e8-4b7905fdcb37/lilugavofaburafudik.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/37a83224-841f-494a-8dbf-f6119e57a8c4/how_to_hook_up_my_home_theater_system.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/a903939d-d369-4be1-aa31-d5ba030c7f0f/dewalt_cordless_tools_combo_kits.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/02775ed5-54de-40ab-ab11-4175e4acf139/the_only_ekg_book_youll_ever_need.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/22050c0d-848b-4c35-a39c-45610d8cf82c/bikenines.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/24becd18-bc6f-4079-90f9-db98f27ce151/zuwetadi.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/72e9d12a-5643-4716-90ec-58faebeb823d/how_to_put_iphone_4s_in_recovery_mode_without_home_button.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

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000da01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA01 5616 bytes
SHA-256: d700f81cdb366071a4d72d367d0111ff4d2d7519d4f7e873fe7b9ea70ef74fdb
font_01_sfnt_off0000ed12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED12 11372 bytes
SHA-256: 93c220f613d235fca2cc4f9fea0573f1122174944251180c47c268c1d530e10f
font_02_sfnt_off0001133f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1133F 4324 bytes
SHA-256: a542ec26cea93e049a2e27cd59b1347dd9bbdea13775fd7b822b3c2b3136116f