Malicious PDF — malware analysis report

Static analysis result for SHA-256 0161cabd7791fb41…

MALICIOUS

PDF

46.4 KB Created: 2020-08-13 08:10:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 818ebc14b4aadb25a4d5b6497908b366 SHA-1: 8e513d2504cc0a39037a41fbdd0953facb790bb5 SHA-256: 0161cabd7791fb41d795e887e92991a2fb0179fc505c49bb21af7559b234395c
154 Risk Score

Malware Insights

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

The PDF contains a link farm designed to redirect users to malicious infrastructure, specifically identified by the critical heuristic PDF_MALICIOUS_REDIRECTOR_LINK. The document body, though heavily obfuscated, contains the URL https://ttraff.ru/wb?keyword=bearing%20calculation%20pdf, suggesting a lure related to technical documents. The ML classifier also strongly indicated 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.ru/wb?keyword=bearing%20calculation%20pdf
    • http://pumewo.brendadater.com/uploads/1/3/2/7/132741024/1fec1ad1.pdf
    • http://xujikuk.adaughterscareassistedliving.com/uploads/1/3/2/6/132682883/8fe3364.pdf
    • http://files.stmarybythesea.com/uploads/1/3/0/7/130739059/399ab73d8a32.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0429/7841/0655/files/goxugakajunewew.pdf
    • https://cdn.shopify.com/s/files/1/0431/9959/4656/files/49274607172.pdf
    • https://cdn.shopify.com/s/files/1/0429/0704/1959/files/miwuvirudunoweni.pdf
    • https://cdn.shopify.com/s/files/1/0431/0191/3244/files/gupajefewimivemukori.pdf
    • https://cdn.shopify.com/s/files/1/0438/3732/5462/files/pogulalofosanituwadar.pdf
    • https://cdn.shopify.com/s/files/1/0438/4745/0789/files/300_accords_guitare.pdf
    • https://cdn.shopify.com/s/files/1/0432/6821/0852/files/wutixaledimipulepagewexa.pdf
    • https://cdn.shopify.com/s/files/1/0434/2421/9293/files/xukijurasa.pdf
    • https://cdn.shopify.com/s/files/1/0433/6818/6015/files/54380942472.pdf
    • https://cdn.shopify.com/s/files/1/0434/3886/6597/files/48725898891.pdf
    • https://cdn.shopify.com/s/files/1/0431/5440/7578/files/safijurujafesakixunoda.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_off00007856.bin
55a96e7fb8817dea882d07754f76ef7e4b80f4eee0d83b849ae33643d1ea810e
pdf-font-stream PDF embedded font (sfnt) at offset 0x7856 5196 bytes
font_01_sfnt_off00008a08.bin
b159e331a3b370658aba0cea498159c4e4764289957dcd7f5b27b97399f936e3
pdf-font-stream PDF embedded font (sfnt) at offset 0x8A08 10320 bytes