Malicious PDF — malware analysis report

Static analysis result for SHA-256 76850f5851869d81…

MALICIOUS

PDF

43.1 KB Created: 2020-08-05 15:29:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 307f9bd7793985cda0388e3bea29b209 SHA-1: 50ac394cd13a68d35089e3c9035868c9ba250f4e SHA-256: 76850f5851869d814cc905818295967c39fd5b89fac378cccf89d4108c48911a
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, contains a URL that mirrors the malicious redirector, suggesting an attempt to disguise the malicious destination. The presence of a link farm indicates a potential SEO poisoning or spamming campaign.

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=cateterismo+venoso+umbilical+pdf
    • http://files.brookrayart.com/uploads/1/3/0/7/130739704/4776625.pdf
    • http://files.nativetales.com/uploads/1/3/0/7/130775942/b90bae542e.pdf
    • http://files.chaseaviation.com/uploads/1/3/1/4/131453144/5744600.pdf
    • http://files.roryfitzgeraldbledsoe.com/uploads/1/3/1/0/131070113/sajirezolisuwagekesa.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0433/6667/8686/files/76376080438.pdf
    • https://cdn.shopify.com/s/files/1/0434/5656/1318/files/67224258679.pdf
    • https://cdn.shopify.com/s/files/1/0431/5804/4827/files/vinivovojovala.pdf
    • https://cdn.shopify.com/s/files/1/0432/0516/5216/files/devirununilaniwetebo.pdf
    • https://cdn.shopify.com/s/files/1/0438/6032/8608/files/79571590633.pdf
    • https://cdn.shopify.com/s/files/1/0431/0653/3525/files/sedenusifipezojemozipatun.pdf
    • https://cdn.shopify.com/s/files/1/0436/2698/7680/files/mokexizenonudupejulixitaw.pdf
    • https://cdn.shopify.com/s/files/1/0431/9143/5422/files/vumufaduwurapefozofarit.pdf
    • https://cdn.shopify.com/s/files/1/0436/8757/5705/files/danoravise.pdf
    • https://cdn.shopify.com/s/files/1/0440/5932/8662/files/nihon_shoki.pdf
    • https://cdn.shopify.com/s/files/1/0432/5064/7204/files/74109282723.pdf
    • https://cdn.shopify.com/s/files/1/0428/6673/7311/files/80453116644.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_off00006a27.bin
b3a1ac85cd1937f26e68837b96604cd9e707444c5b4523daafadd45ac433532c
pdf-font-stream PDF embedded font (sfnt) at offset 0x6A27 5408 bytes
font_01_sfnt_off00007c71.bin
c95406ec2e75b2747f3e98b864f114186b325a264ee39f885759a8dc064af846
pdf-font-stream PDF embedded font (sfnt) at offset 0x7C71 10376 bytes