Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2474885ba2ca05a…

MALICIOUS

PDF

68.6 KB Created: 2020-11-24 07:02:06 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 550efd49b39ddf0d6ac209767903003a SHA-1: 952dd75a4b66066e482466a8be6ac355e9ceefde SHA-256: b2474885ba2ca05a4e756d5ff06777a6456f3c228f1bde4fee918bece01715e2
156 Risk Score

Malware Insights

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

The PDF contains a large number of external links, identified as a link farm, suggesting a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly indicate malicious intent. While no scripts were explicitly extracted, the PDF structure and numerous external URLs point towards a malicious document, likely delivered via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://trafffe.ru/strik?utm_term=fluid+mechanics+by+rk+bansal+for+civil+engineering
    • https://cdn-cms.f-static.net/uploads/4381320/normal_5f9564221038f.pdf
    • https://cdn-cms.f-static.net/uploads/4487918/normal_5fb99add61712.pdf
    • https://fomukudir.weebly.com/uploads/1/3/4/4/134403856/kamoxura_lereji_lefemimuwonexad.pdf
    • https://wavixupenug.weebly.com/uploads/1/3/4/3/134386336/48689e11c4.pdf
    • https://cdn-cms.f-static.net/uploads/4391037/normal_5f988378b5d34.pdf
    • https://ledewamigov.weebly.com/uploads/1/3/4/8/134850019/6cf69c9844.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/1f20b7cd-09f7-4ea7-aa01-73ad712cde63/t24c550nd_samsung_tv_manual.pdf
    • https://s3.amazonaws.com/lixuzo/print_webpage_to_ipad.pdf
    • https://uploads.strikinglycdn.com/files/2b3fa5ae-96f3-4f6e-befb-a663aa6d984d/3572697553.pdf
    • https://uploads.strikinglycdn.com/files/8b7a8fda-1dd9-49b7-9841-021962a854d8/wazixibibe.pdf
    • https://s3.amazonaws.com/lunojol/redmi_note_7_camera_apk.pdf
    • https://uploads.strikinglycdn.com/files/583751d6-aa33-4578-952f-6fa30e30d746/essential_environment_the_science_behind_the_stories_5th_edition.pdf
    • https://uploads.strikinglycdn.com/files/225d554f-bb09-45ac-b69a-69f4b0264001/61749635927.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_off0000cf3e.bin
48668ad7f21a3fda7543aba1784be26b43b51038534d7c42cd13bb650da65359
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF3E 5756 bytes
font_01_sfnt_off0000e2b3.bin
45658b5597453f253a758a5db21e499ec7a310f6f87dac8fed2062d3ce1f7260
pdf-font-stream PDF embedded font (sfnt) at offset 0xE2B3 10160 bytes