Malicious PDF — malware analysis report

Static analysis result for SHA-256 42031ab6d7683987…

MALICIOUS

PDF

46.7 KB Created: 2020-07-31 11:45:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 12d215cff11aa6469b2fcc6f83cf2641 SHA-1: 807987c2dbf494745efb2a816eb441afac8b79cb SHA-256: 42031ab6d768398784ad03de455827f4e4b2a4ee2fb4dcb189e342648190c5ee
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which point to a redirector service (ttraff.ru). The ML classifier strongly indicates maliciousness. The document body, though heavily obfuscated, contains metadata suggesting it was generated by wkhtmltopdf, a tool often used to create documents for SEO spam or phishing lures. The primary attack vector appears to be directing users to malicious or spam-related websites through the embedded link farm.

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=social+ontology+and+modern+economics+pdf
    • http://files.mlabca.com/uploads/1/3/1/8/131857465/1e571a.pdf
    • http://files.lumbercityfarmday.org/uploads/1/3/0/9/130969389/9741664.pdf
    • http://files.carrwriter.com/uploads/1/3/1/6/131606954/nujir_totegov.pdf
    • http://files.globalafricadiaspora.org/uploads/1/3/0/8/130874307/wuvov_mijalavovusese_gulolaxizirufu_xovemes.pdf
    • https://cdn.shopify.com/s/files/1/0432/6601/5395/files/pewejife.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/bopeberovejaxurid.pdf
    • https://cdn.shopify.com/s/files/1/0432/8249/7701/files/27382868749.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/33374625424.pdf
    • https://cdn.shopify.com/s/files/1/0434/9342/5316/files/lumozigotijan.pdf
    • https://cdn.shopify.com/s/files/1/0431/7747/6260/files/zinipinuworu.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/94662163826.pdf
    • https://cdn.shopify.com/s/files/1/0435/7767/1843/files/86398487158.pdf
    • https://cdn.shopify.com/s/files/1/0431/7547/7405/files/8220631985.pdf
    • https://cdn.shopify.com/s/files/1/0428/6346/0508/files/75405544507.pdf
    • https://cdn.shopify.com/s/files/1/0432/6031/3763/files/xukokolibopojijuvadino.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_off000077cc.bin
c96745f2d5639faa9035232e7dd71e4627e84ff672812a97e0c3eaf4eaae8779
pdf-font-stream PDF embedded font (sfnt) at offset 0x77CC 5468 bytes
font_01_sfnt_off00008a3c.bin
e014044288159ca54fe4f14ffda7dc11c7e943bbc0092afa932401133b967451
pdf-font-stream PDF embedded font (sfnt) at offset 0x8A3C 10168 bytes