Malicious PDF — malware analysis report

Static analysis result for SHA-256 2874b2c13c82f490…

MALICIOUS

PDF

40.8 KB Created: 2020-08-20 12:38:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1ff80a3bd5abe517b2c5148b9c5a2afb SHA-1: 2e2f53c39e043bed817656e88b15bebd3a6b0170 SHA-256: 2874b2c13c82f4909e5162766159c73919d49908011f7aa3d8a0123f7f7d6377
154 Risk Score

Malware Insights

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

The PDF contains a link farm, with one prominent URL pointing to a known malicious redirector. The document body, though partially garbled, includes text related to 'virtual assistant skills test answers' and the malicious URL, suggesting a lure to a phishing or malware distribution site. The ML classifier strongly flagged this PDF as malicious.

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/pify?keyword=virtual+assistant+skills+test+2017+answers
    • http://misefiz.cambridgeintlschool.com/uploads/1/3/1/3/131383541/bced432f6.pdf
    • http://files.localcraft.net/uploads/1/3/0/9/130969851/mukopa.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/siwizobudavegi.pdf
    • https://cdn.shopify.com/s/files/1/0434/1671/5429/files/xilolu.pdf
    • https://cdn.shopify.com/s/files/1/0438/3778/4224/files/18743083951.pdf
    • https://cdn.shopify.com/s/files/1/0437/9125/3653/files/77670138402.pdf
    • https://cdn.shopify.com/s/files/1/0438/3955/3696/files/73062251110.pdf
    • https://cdn.shopify.com/s/files/1/0432/0896/6301/files/89797718798.pdf
    • https://cdn.shopify.com/s/files/1/0430/9532/6887/files/16752748189.pdf
    • https://cdn.shopify.com/s/files/1/0432/2089/3864/files/common_functional_groups.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/baludugosutagaxoreforodul.pdf
    • https://cdn.shopify.com/s/files/1/0431/8861/7378/files/xelebofamalokez.pdf
    • https://cdn.shopify.com/s/files/1/0432/7918/8118/files/88908758534.pdf
    • https://cdn.shopify.com/s/files/1/0434/6196/8025/files/informe_de_enlaces_quimicos.pdf
    • https://cdn.shopify.com/s/files/1/0430/5698/8317/files/dosarat.pdf
    • https://cdn.shopify.com/s/files/1/0431/5339/1780/files/35111089817.pdf
    • https://cdn.shopify.com/s/files/1/0435/1826/3448/files/tabuvexesixol.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_off00006156.bin
a3c370528e4a8600cfe70cae7fbada4dda49258370e9d2ad4b9b5768d12f4f11
pdf-font-stream PDF embedded font (sfnt) at offset 0x6156 5208 bytes
font_01_sfnt_off0000733d.bin
dcddf786365df1a5dc41f6fa031624da8552df0cbd062f9640c409c1e6c893a0
pdf-font-stream PDF embedded font (sfnt) at offset 0x733D 10284 bytes