Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c7227a60483654a…

MALICIOUS

PDF

46.5 KB Created: 2020-07-26 12:01:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9647409c7f2547cec1609988c76a5699 SHA-1: 990234d377f9fb437bfd7b9d3416744df100c7bd SHA-256: 5c7227a60483654af037b5602412a5307ccff56970f4179b91ca556404101b5c
162 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1203 Exploitation for Client Execution

The PDF contains a link farm and a redirector link, indicating a phishing or scam attempt. The ML classifier strongly flagged this PDF as malicious. The document body, though heavily obfuscated, contains text related to 'Bluestacks offline installer old version' and mentions 'wkhtmltopdf', suggesting a lure to download potentially unwanted or malicious software. The presence of numerous external PDF links further supports a link farm strategy.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=bluestacks+offline+installer+old+version
    • http://files.trackfourjournal.com/uploads/1/3/2/7/132740515/e966fa.pdf
    • http://files.williamsburgnaz.org/uploads/1/3/1/4/131410479/7335e5fc7bfdae2.pdf
    • http://files.bviark.org/uploads/1/3/1/4/131437813/0fc3f512.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0430/2739/8807/files/jisumexufukakigexa.pdf
    • https://cdn.shopify.com/s/files/1/0431/0417/4233/files/mamibobozoladedadusimobe.pdf
    • https://cdn.shopify.com/s/files/1/0435/6905/3854/files/todoramupokegililomi.pdf
    • https://cdn.shopify.com/s/files/1/0434/0803/1893/files/buronikulomevijanowof.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/9959313526.pdf
    • https://cdn.shopify.com/s/files/1/0434/9113/1557/files/96333330051.pdf
    • https://cdn.shopify.com/s/files/1/0435/4116/8283/files/65888083801.pdf
    • https://cdn.shopify.com/s/files/1/0432/7469/8902/files/16690898864.pdf
    • https://cdn.shopify.com/s/files/1/0436/9511/2347/files/12743830093.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_off00007811.bin
f1b19818d12d963a1a841b229dd745dc4ae108509f6f82e8fb569bde490d053f
pdf-font-stream PDF embedded font (sfnt) at offset 0x7811 5072 bytes
font_01_sfnt_off0000895b.bin
136e1a915ec0a3219ca75a2a1198de5b8782b0d5a60a526b0db9329d852651c5
pdf-font-stream PDF embedded font (sfnt) at offset 0x895B 10328 bytes