Malicious PDF — malware analysis report

Static analysis result for SHA-256 41ba7d5438f9d15c…

MALICIOUS

PDF

34.4 KB Created: 2020-08-03 02:32:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e9f1cc6be66a17b31c979a19340292df SHA-1: 6aa0894b01820f6c5f54bf519a0194597da526dc SHA-256: 41ba7d5438f9d15c8a4dcd030f24e57c5f2c34211d3a4c32fd569c571e9ed5e7
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.cc, which is presented as a 'bleep sound effect download'. The document also functions as a link farm, directing users to numerous other PDFs hosted on various domains, many of which are dynamically generated or use numeric slugs, suggesting a SEO poisoning or link farm tactic. The ML classifier 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.cc/pify?keyword=bleep+sound+effect+download
    • http://files.cypbb.com/uploads/1/3/0/7/130775192/3a7ce22b9d48e8.pdf
    • http://files.hammellwinealliance.com/uploads/1/3/2/6/132695575/d00818ffd3e.pdf
    • http://files.daisyhillgoats.com/uploads/1/3/0/9/130969855/fagajawerowiz-jasewonimaxar-fikama.pdf
    • http://files.loveandorthodontics.com/uploads/1/3/0/7/130740017/zejipater.pdf
    • https://cdn.shopify.com/s/files/1/0429/3237/1622/files/46962580699.pdf
    • https://cdn.shopify.com/s/files/1/0433/0638/5573/files/topus.pdf
    • https://cdn.shopify.com/s/files/1/0431/1128/4893/files/wilexopexinule.pdf
    • https://cdn.shopify.com/s/files/1/0431/2186/8960/files/zuzududunosukovunuvebuk.pdf
    • https://cdn.shopify.com/s/files/1/0431/7764/0093/files/bozurifagemobidemakovid.pdf
    • https://cdn.shopify.com/s/files/1/0431/3153/5524/files/70381955721.pdf
    • https://cdn.shopify.com/s/files/1/0438/5816/5925/files/tanka_poetry_example.pdf
    • https://cdn.shopify.com/s/files/1/0429/2309/8279/files/kubota_b7800_for_sale.pdf
    • https://cdn.shopify.com/s/files/1/0433/7562/4350/files/91896031094.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/81667611697.pdf
    • https://cdn.shopify.com/s/files/1/0437/3735/0293/files/55707101487.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_off00004a17.bin
64d7e36f406d8ef676377dfa7858d23e085ccac3e0379faa0f9a19f2d632251a
pdf-font-stream PDF embedded font (sfnt) at offset 0x4A17 5196 bytes
font_01_sfnt_off00005bf4.bin
d1f64fdf9d9d8573eb66f995feb2947d10b22a9620ce6cdcb1fc6bd562c67cf7
pdf-font-stream PDF embedded font (sfnt) at offset 0x5BF4 9640 bytes