Malicious PDF — malware analysis report

Static analysis result for SHA-256 6921261bfa7af5d1…

MALICIOUS

PDF

33.8 KB Created: 2020-08-31 01:50:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0138fbde0a0ffe45ee61cb4fa73e6a8c SHA-1: 6c1ebacd519c59178ab850393a0734fc63cfe507 SHA-256: 6921261bfa7af5d192293894f62eae2cf50b380fdf230464838d8f383eb02ec1
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged as malicious by a machine learning classifier and contains a link to a known malicious redirector. It also features a large number of embedded links, many pointing to Shopify, which is characteristic of SEO link farm abuse. The document body contains a mixture of seemingly unrelated text and URLs, further supporting the link farm hypothesis.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • 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.
  • 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://ttraff.ru/wix?keyword=my+hero+academia+season+2+episode+3+dubbed
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0438/5452/8677/files/railway_group_d_allahabad_answer_key_2018.pdf
    • https://cdn.shopify.com/s/files/1/0431/4333/2000/files/physics_formulas_pdf_for_eamcet.pdf
    • https://cdn.shopify.com/s/files/1/0443/6908/4572/files/phone_call_app_free.pdf
    • https://cdn.shopify.com/s/files/1/0434/6707/9830/files/87645047852.pdf
    • https://cdn.shopify.com/s/files/1/0427/8226/1415/files/10020102361.pdf
    • https://cdn.shopify.com/s/files/1/0431/3723/7146/files/tmnt_2007_pc_game_setup_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0437/9171/2405/files/additional_mathematics_syllabus.pdf
    • https://cdn.shopify.com/s/files/1/0429/2358/9791/files/breakfast_burrito_nutrition_information.pdf
    • https://cdn.shopify.com/s/files/1/0438/9303/1080/files/fodisivaluxomiwas.pdf
    • https://cdn.shopify.com/s/files/1/0435/5496/3617/files/aptoide_tv_apk_old_version.pdf
    • https://cdn.shopify.com/s/files/1/0429/2925/8649/files/lupizatixezile.pdf
    • https://static.usrfiles.com/ugd/bd5c68_bd2e89843fad41748cd0b00263ead300.pdf
    • https://static.usrfiles.com/ugd/a31856_3cf3a767fa78418cb7ec1fa14eb7f461.pdf
    • https://static.usrfiles.com/ugd/26481d_565dcfa0fbb4432f92edea1ad2c6b4a7.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_off0000452e.bin
33e62e15fa87911f7762a0e2131a267fdb7ea1bc7c3ea5eef0d6431dfb2a9c88
pdf-font-stream PDF embedded font (sfnt) at offset 0x452E 5824 bytes
font_01_sfnt_off000058dd.bin
3283e5ff3245ee9da9c0189bd4fdff8299b21e15194745724ec137487557321b
pdf-font-stream PDF embedded font (sfnt) at offset 0x58DD 9812 bytes