Malicious PDF — malware analysis report

Static analysis result for SHA-256 4251a645dd3a8b81…

MALICIOUS

PDF

42.7 KB Created: 2020-08-22 22:17:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dbdadb0f0b62d7db69a506799ed23ed6 SHA-1: b3ae702a7b09b5704eb3bf3c5b2ae207808ea1b2 SHA-256: 4251a645dd3a8b81dd59e6b74ccf430810e2e6e84a12b080ff0212059fe3ed0f
154 Risk Score

Malware Insights

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

The PDF contains embedded links that redirect to a malicious URL, specifically designed to mimic a Google Docs fillable form. The ML classifier strongly indicates maliciousness. The primary malicious IOC is the redirector URL, which is used to lure victims. The PDF also hosts a large number of other links, many pointing to Shopify, likely as part of a link farm to improve search engine ranking for malicious content.

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=google+docs+fillable+forms
    • http://files.djwindowcleaning.com/uploads/1/3/0/8/130874678/tobubilobumatipu.pdf
    • http://zekeg.raamarchant.com/uploads/1/3/2/6/132695550/filaj.pdf
    • http://vusedu.mccreaproductions.com/uploads/1/3/0/9/130969744/rijizafowugijadu.pdf
    • http://files.match-gems.com/uploads/1/3/2/7/132740598/913690.pdf
    • http://liwajabab.juliejeanseau.com/uploads/1/3/2/6/132696021/buvunalomosod_pibajabe_raseraxif_muwofetetefamap.pdf
    • https://cdn.shopify.com/s/files/1/0430/2431/8618/files/92303851821.pdf
    • https://cdn.shopify.com/s/files/1/0435/1331/5480/files/78580114671.pdf
    • https://cdn.shopify.com/s/files/1/0430/7209/4362/files/modelo_biopsicosocial_psicologia.pdf
    • https://cdn.shopify.com/s/files/1/0432/1171/8820/files/39230310634.pdf
    • https://cdn.shopify.com/s/files/1/0432/8977/2187/files/repetitive_dna_sequences.pdf
    • https://cdn.shopify.com/s/files/1/0430/4994/3202/files/bokivalikizuvuvapowol.pdf
    • https://cdn.shopify.com/s/files/1/0435/2308/0344/files/cool_answering_machine_messages_audio.pdf
    • https://cdn.shopify.com/s/files/1/0429/6130/5756/files/78439465803.pdf
    • https://cdn.shopify.com/s/files/1/0431/9451/5614/files/51687589381.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
font_00_sfnt_off00005aa0.bin
33ef78244258972a2f8dfa32d14f7d10f03c7c4f2ee3ea4ead2179d98c16557d
pdf-font-stream PDF embedded font (sfnt) at offset 0x5AA0 5116 bytes
font_01_sfnt_off00006c03.bin
a840d9961da00071fb65ba4b72d46b6819216682a9a3cd225fc280fcd1df204b
pdf-font-stream PDF embedded font (sfnt) at offset 0x6C03 10488 bytes
font_02_sfnt_off00008ff8.bin
d1f4a20f0e35a0564be54678b929bb8c711862c507f070c2b9a6abea8daf4378
pdf-font-stream PDF embedded font (sfnt) at offset 0x8FF8 4324 bytes