Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f787b65de738db2…

MALICIOUS

PDF

64.6 KB Created: 2020-08-19 10:31:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d59cd37ee367de402c0c7a750230a82b SHA-1: 0e8e5c0defde539b595efa7a7f9b5575d81970e0 SHA-256: 7f787b65de738db2b2649197812d14f9de2acfe2ec3fafdc07114e5cf0572984
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains a mass external link farm, with a primary malicious redirector disguised as a book download. The link `https://ttraff.ru/pify?keyword=representation+theory+book+pdf` leads to known malicious infrastructure. The presence of numerous Shopify-hosted PDF links suggests an attempt to create a large, seemingly legitimate link farm to obscure the malicious redirector. The ML classifier strongly supports the malicious verdict.

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/pify?keyword=representation+theory+book+pdf
    • http://files.smilesensations.ca/uploads/1/3/1/4/131406950/747358.pdf
    • http://xinov.thepelham.net/uploads/1/3/0/9/130969060/xusexosinip.pdf
    • http://files.scituateriltcc.org/uploads/1/3/0/8/130814121/vivegepaxe.pdf
    • https://cdn.shopify.com/s/files/1/0430/6350/9143/files/whatsapp_business_app_for_laptop.pdf
    • https://cdn.shopify.com/s/files/1/0441/2683/0744/files/77136812250.pdf
    • https://cdn.shopify.com/s/files/1/0434/8434/8569/files/program_to_edit_documents_free.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/vazakiliduvapi.pdf
    • https://cdn.shopify.com/s/files/1/0437/6074/6648/files/lagemaxovumav.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/puliwaxaj.pdf
    • https://cdn.shopify.com/s/files/1/0437/6795/5610/files/schindler_s_list_book_free.pdf
    • https://cdn.shopify.com/s/files/1/0430/7750/1079/files/81817003546.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/

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_003_off000062f1.bin
24638ca2437d417fd014d4820f532e8a6b10b71dc26819e970e21bd546673c28
decompressed-pdf-stream PDF FlateDecoded stream at offset 0x62F1 30296 bytes
font_01_sfnt_off0000c069.bin
52240e7c7c06a13693d4426153b97ad6148e235f473c10af2d8eb0e1cac4ed0f
pdf-font-stream PDF embedded font (sfnt) at offset 0xC069 5412 bytes
font_02_sfnt_off0000d2cb.bin
c4c3834a531a262f9da5bcaa199c020e659179ab50e39ebc1818f61fa5e061b3
pdf-font-stream PDF embedded font (sfnt) at offset 0xD2CB 10236 bytes