Malicious PDF — malware analysis report

Static analysis result for SHA-256 13523afe79b942e4…

MALICIOUS

PDF

40.8 KB Created: 2020-08-23 11:45:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: b68d7f251d0e7a0733fb40ea5f6ccfaf SHA-1: cdff70d1f9d665a91a7392483ee7cca649ef8b19 SHA-256: 13523afe79b942e49161397494d66f1cc00ecbcaa197369ee57260e8f8048ec7
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a link to a known malicious redirector, indicating an attempt to lead the user to harmful content. It also functions as a link farm, distributing numerous external PDF links, many of which are hosted on Shopify. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is designed for malicious redirection.

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=basic+english+grammar+rules+cheat+sheet
    • http://vuruji.briansweetdesign.com/uploads/1/3/0/7/130775169/wudilisiper.pdf
    • http://files.wickedsweetrentals.com/uploads/1/3/1/4/131483214/gifojasapexor_melam_rilome.pdf
    • http://files.libertyshelties.com/uploads/1/3/2/8/132816202/58eefa.pdf
    • http://files.mayusaeki.com/uploads/1/3/0/8/130873880/a31fee30b.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/5670/9288/files/18979724164.pdf
    • https://cdn.shopify.com/s/files/1/0428/1240/7967/files/68175064052.pdf
    • https://cdn.shopify.com/s/files/1/0449/9701/7768/files/professional_baking_6th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0440/1243/7662/files/bagri_market_fire_accident_report_writing.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/98774508290.pdf
    • https://cdn.shopify.com/s/files/1/0439/0024/0024/files/35093221919.pdf
    • https://cdn.shopify.com/s/files/1/0439/9448/0798/files/terraform_aws_iam_policy_document_example.pdf
    • https://cdn.shopify.com/s/files/1/0434/4299/5367/files/kurenaz.pdf
    • https://cdn.shopify.com/s/files/1/0432/5575/9011/files/budget_sheet_printable.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_off00006218.bin
60eeedea50b9ecfabd69dcec6fc77cfcd6d9f6fa5cb3cbdcc440c030dd729798
pdf-font-stream PDF embedded font (sfnt) at offset 0x6218 5264 bytes
font_01_sfnt_off000073c2.bin
bac64e67c326375732c31a68a89dbbd579a8f952871ad897073747e89847fc09
pdf-font-stream PDF embedded font (sfnt) at offset 0x73C2 10072 bytes