Malicious PDF — malware analysis report

Static analysis result for SHA-256 85bf73ca936e006d…

MALICIOUS

PDF

31.7 KB Created: 2020-08-21 01:59:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d7e9f9eb397878e1304e4e9741bcabef SHA-1: 23a56377e5cb6688c0c0923125f5f458184cce7d SHA-256: 85bf73ca936e006df3f0d1e309306be89abc5f367b4e7c38e9f4ffb443a7b71d
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link, disguised as a 'Bahubali 2 wallpaper full hd' download. The document body, though heavily obfuscated, also contains this URL. The presence of numerous other PDF links, many pointing to Shopify domains, suggests a link farm or SEO poisoning tactic to distribute the malicious content. The ML classifier strongly supports the malicious nature of this PDF.

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.com/pify?keyword=bahubali+2+wallpaper+full+hd
    • http://raxigasi.sdcecd.com/uploads/1/3/0/7/130775164/c4489e32a5ae.pdf
    • http://files.topsailrigging.com/uploads/1/3/0/8/130815095/2021793.pdf
    • http://mired.pickphysics.com/uploads/1/3/0/7/130775027/rikagajonedew_wuberifekez_lejimikepusep_durab.pdf
    • https://cdn.shopify.com/s/files/1/0439/2094/9403/files/definition_of_sports_psychology.pdf
    • https://cdn.shopify.com/s/files/1/0435/9726/7112/files/laravel_html_to_package.pdf
    • https://cdn.shopify.com/s/files/1/0429/7831/2355/files/gosivuxevurutoner.pdf
    • https://cdn.shopify.com/s/files/1/0434/1393/0142/files/natotiwinezodoxazawubibi.pdf
    • https://cdn.shopify.com/s/files/1/0434/0524/6631/files/lupedopixopetugamatike.pdf
    • https://cdn.shopify.com/s/files/1/0428/3600/0931/files/70346444346.pdf
    • https://cdn.shopify.com/s/files/1/0429/7955/7539/files/9450338440.pdf
    • https://cdn.shopify.com/s/files/1/0428/4976/3494/files/fazomemugeza.pdf
    • https://cdn.shopify.com/s/files/1/0430/2438/4154/files/long_sleeve_t_shirt_template_design.pdf
    • https://cdn.shopify.com/s/files/1/0432/8554/5124/files/6742653845.pdf
    • https://cdn.shopify.com/s/files/1/0441/0654/7352/files/15843261714.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004109.bin
4a9770f7d73ba48aceb68b940abda15b3a3d6e6cefd1ddcd50b041cebee1258d
pdf-font-stream PDF embedded font (sfnt) at offset 0x4109 5364 bytes
font_01_sfnt_off00005354.bin
84e5f4f1a36e6673c0dd18fdc5f54a4b09912320f4b01d33029beddf5b78993a
pdf-font-stream PDF embedded font (sfnt) at offset 0x5354 9068 bytes