Malicious PDF — malware analysis report

Static analysis result for SHA-256 c87bab1adee3dd53…

MALICIOUS

PDF

88.4 KB Created: 2021-05-23 20:06:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 37b368eb8103f96504892c6b83642e73 SHA-1: e2161fe43c89e4c6fab74490406c35c4f24993b1 SHA-256: c87bab1adee3dd537f7278e33e515cd598e21fa4523220625e68d455a44455d3
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, as indicated by the PDF_SEO_LINK_FARM heuristic, suggesting a link farm or phishing attempt. The ML classifier and ClamAV detection strongly indicate malicious intent. While no scripts were explicitly extracted, the presence of numerous external links points towards a malicious document, likely used as a lure to redirect users to potentially harmful sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://pelibifir.ru/strik?utm_term=ecological+pyramid+with+four+trophic+levels
    • https://zadumujiz.weebly.com/uploads/1/3/4/6/134626950/9430547.pdf
    • https://likuwiwekadu.weebly.com/uploads/1/3/1/8/131857000/b5e1fafd.pdf
    • https://gefawopunov.weebly.com/uploads/1/3/0/9/130969454/zebaledipejomelema.pdf
    • https://palezagedubegiw.weebly.com/uploads/1/3/4/0/134017965/8684436.pdf
    • https://mafoxoluz.weebly.com/uploads/1/3/1/4/131483222/darapobefipakageba.pdf
    • https://tadirexexex.weebly.com/uploads/1/3/2/6/132695418/2b1667491bf8943.pdf
    • https://sokufadatapa.weebly.com/uploads/1/3/4/4/134474271/xejajuxalerokedubuve.pdf
    • https://vebavorosufate.weebly.com/uploads/1/3/4/7/134742301/3674443.pdf
    • https://mulidugegobivim.weebly.com/uploads/1/3/4/3/134318636/kegavifope_bokarorunefifu.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/zarelusipofox/18164159030.pdf
    • https://s3.amazonaws.com/dazinibonofobi/puginibukivusop.pdf
    • https://uploads.strikinglycdn.com/files/19803293-ca0e-4605-b3f7-e53ebed4d926/laparigomapatujawo.pdf
    • https://uploads.strikinglycdn.com/files/11499c33-6681-4150-a497-5d3ea3d7afa5/puvewoja.pdf
    • https://s3.amazonaws.com/kefodek/furewobo.pdf
    • https://s3.amazonaws.com/fekazudabo/winchester_model_94ae_357_mag_saddle_ring_carbine.pdf
    • https://s3.amazonaws.com/sinamozagemoger/wokela.pdf
    • https://uploads.strikinglycdn.com/files/13397ad7-acce-4321-889b-207d5a1f370c/50644155478.pdf
    • https://s3.amazonaws.com/pujinit/ferijafutanisujamobo.pdf
    • https://s3.amazonaws.com/xijalovelokolep/catalyst_2960-_l_switch_hardware_installation_guide.pdf
    • https://uploads.strikinglycdn.com/files/fb09b788-73a2-4273-ab34-bf6badd19b83/giwiwavurupobudotonaxefe.pdf
    • https://s3.amazonaws.com/wulagisi/how_to_get_started_writing_a_screenplay.pdf
    • https://s3.amazonaws.com/fidefofudi/1311551810.pdf
    • https://s3.amazonaws.com/suxuzubojut/cement_manufacturing_project.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00011b69.bin
4b27be4f1dbb0aac835122c7d53b40ac8daa6875b555df9d064989b71d066d90
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B69 5780 bytes
font_01_sfnt_off00012f0f.bin
6530255472e754cfca6ec9a4521af670ba55fc0b41cfca4685ec0b8003f2a245
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F0F 10844 bytes