Malicious PDF — malware analysis report

Static analysis result for SHA-256 319f45f1b2e61b24…

MALICIOUS

PDF

71.3 KB Created: 2021-04-08 04:31:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 20358fc2b46422929e52050458538ee8 SHA-1: dd9b71e5c7c466ca509aa15fd64504ca807fc88b SHA-256: 319f45f1b2e61b249e13c4575c8f611fdbbb79fce4bf5b6a3345f07e60daace2
156 Risk Score

Malware Insights

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

The PDF file contains a significant number of external links, identified as a 'PDF_SEO_LINK_FARM' heuristic. One of these links, 'https://golowaki.ru/123?utm_term=bootstrap+mobile+cards+template', is directly embedded. ClamAV also detected this file as 'Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0'. The presence of numerous external links suggests a phishing or malicious redirection attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

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://golowaki.ru/123?utm_term=bootstrap+mobile+cards+template
    • https://cdn-cms.f-static.net/uploads/4375708/normal_60142cd958b4f.pdf
    • https://cdn-cms.f-static.net/uploads/4470692/normal_60275c9738023.pdf
    • https://nilesezijifata.weebly.com/uploads/1/3/4/8/134885493/5235674.pdf
    • https://cdn-cms.f-static.net/uploads/4387712/normal_602a4c93b632e.pdf
    • https://static.s123-cdn-static.com/uploads/4389792/normal_5fdfc7a20c966.pdf
    • https://cdn-cms.f-static.net/uploads/4481166/normal_603c2e7212412.pdf
    • http://nowanedilado.22web.org/kobalt_30_gallon_air_compressor_oil_type.pdf
    • https://cdn-cms.f-static.net/uploads/4475728/normal_6056b10f7e635.pdf
    • https://bitekiparoduj.weebly.com/uploads/1/3/4/0/134017536/d841169730c702.pdf
    • https://cdn-cms.f-static.net/uploads/4450636/normal_6055309092993.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://s3.amazonaws.com/wajibile/92249161984.pdf
    • https://s3.amazonaws.com/seriposuj/how_to_tell_if_eotech_512_is_real.pdf
    • https://s3.amazonaws.com/viwoxuz/wojutoduxavukunub.pdf
    • https://s3.amazonaws.com/kibavutibeved/can_you_use_macros_on_excel_online.pdf
    • http://piserujirabubam.epizy.com/cant_see_shortcuts_on_desktop_windows_10.pdf
    • https://s3.amazonaws.com/rovikibixu/what_is_the_best_shampoo_for_very_oily_hair.pdf
    • https://00407fa8-a9ef-4b78-9bbe-46147fc8acf6.filesusr.com/ugd/5ecadc_6b86a2d97c664bf1927519d3eb30726d.pdf?index=true
    • https://0e01c86c-6ad9-43de-bc04-b8819f410213.filesusr.com/ugd/73c254_0a07d3d430594267a8305ea55b32a2cf.pdf?index=true
    • https://cf075d60-af7c-4c71-a16c-5c8c125a9bb7.filesusr.com/ugd/cc03df_9582f69288814fd6817cddf6c5ec7a5c.pdf?index=true
    • http://junixaz.epizy.com/82598681683.pdf
    • https://21e323bd-7fdd-46e9-a6c7-4880e76d7610.filesusr.com/ugd/0a51c1_8d84aa0f645044828bfa97c7360c880c.pdf?index=true
    • https://5f384421-c3d0-4b4c-85a6-d3745974446f.filesusr.com/ugd/40006b_a68591e6dc37490c911eaf5f853a9f3f.pdf?index=true
    • 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_off0000d7e8.bin
8392e3eb80c9b1efe9f204beb855a0ac4931469748a3c2afeb34a4b5c100fe7f
pdf-font-stream PDF embedded font (sfnt) at offset 0xD7E8 5408 bytes
font_01_sfnt_off0000ea2f.bin
ac275343cfac570a12c38616ecd670da965d4f0180924c5b78da012519f0ac9e
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA2F 11192 bytes