Malicious PDF — malware analysis report

Static analysis result for SHA-256 71b391731a573041…

MALICIOUS

PDF

37.4 KB Created: 2020-08-17 18:30:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2ff685f8bdc51df19ad27d822ec2e223 SHA-1: d4fa2c19a508a9d740fa36959530d1a117fd4d5f SHA-256: 71b391731a5730418c76be1e081120d736c986dec918c93d995199f0ee6abefa
154 Risk Score

Malware Insights

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

The PDF contains embedded links designed to redirect users to malicious infrastructure, specifically a link farm. The document body, though partially corrupted, suggests a lure related to 'correlation vs causation worksheet answers'. The primary malicious IOC is the redirector URL, which is likely used to deliver a secondary payload. The ML classifier strongly indicates maliciousness.

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.cc/pify?keyword=correlation+vs+causation+worksheet+answers
    • http://files.distantfin.net/uploads/1/3/0/7/130775734/pamofasusure.pdf
    • http://pufurib.brianmoskin.com/uploads/1/3/0/8/130813108/renesuv_xinot_wizuvunosilabo_dozebisazuv.pdf
    • http://dogekal.malikwork.com/uploads/1/3/2/7/132710712/9511409.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0448/1554/8573/files/lil_shop_of_treasures.pdf
    • https://cdn.shopify.com/s/files/1/0437/5651/9578/files/upsc_ifs_botany_syllabus.pdf
    • https://cdn.shopify.com/s/files/1/0432/8715/0752/files/79178668914.pdf
    • https://cdn.shopify.com/s/files/1/0432/1817/4107/files/bipolar_disorder_patient_case_study.pdf
    • https://cdn.shopify.com/s/files/1/0431/4628/1122/files/2903556348.pdf
    • https://cdn.shopify.com/s/files/1/0436/9930/6648/files/application_letter_for_ojt_sample.pdf
    • https://cdn.shopify.com/s/files/1/0428/1961/6935/files/54148325348.pdf
    • https://cdn.shopify.com/s/files/1/0437/7929/3338/files/50660523633.pdf
    • https://cdn.shopify.com/s/files/1/0432/0421/4942/files/29563144735.pdf
    • https://cdn.shopify.com/s/files/1/0433/9764/4449/files/94826402579.pdf
    • https://cdn.shopify.com/s/files/1/0432/5523/4710/files/77012045602.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_off000055c5.bin
7499fd5aef42de56b2f27731c5d0832b9659e1708c8c1460d8cc10c9b60044cb
pdf-font-stream PDF embedded font (sfnt) at offset 0x55C5 5008 bytes
font_01_sfnt_off000066d5.bin
5105b2be2037d2571941fa76627edaf69d3bfc426d9278b5cac42f9108c99783
pdf-font-stream PDF embedded font (sfnt) at offset 0x66D5 9904 bytes