Malicious PDF — malware analysis report

Static analysis result for SHA-256 823fad78db755e55…

MALICIOUS

PDF

61.1 KB Created: 2020-08-22 02:13:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 6a473bafb11a893ecfe5055ca85332ef SHA-1: 2ada54b67a19308f5ebf811740647b0424151ab7 SHA-256: 823fad78db755e5579a414da441ee4ae999ab508e15d39d41b1dae7f19becc10
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to a redirector service known to host malicious content. The document body also contains a direct link to this redirector, suggesting an attempt to trick users into visiting potentially harmful sites. The ML classifier also 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=socomec+atys+d20+manual
    • http://favukaf.lexialearners.com/uploads/1/3/1/4/131438397/985cd5b.pdf
    • http://files.kelleygrantbooks.com/uploads/1/3/1/8/131856919/busemawen_jabam.pdf
    • http://files.healthyvasquez.com/uploads/1/3/2/8/132814276/sumenikulutib.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0428/6224/8102/files/delitadokurexamutuze.pdf
    • https://cdn.shopify.com/s/files/1/0430/6056/0021/files/muvusuxasegibewulokumu.pdf
    • https://cdn.shopify.com/s/files/1/0431/4346/3074/files/16374263389.pdf
    • https://cdn.shopify.com/s/files/1/0438/7468/0987/files/54235974345.pdf
    • https://cdn.shopify.com/s/files/1/0433/7968/7587/files/9487941803.pdf
    • https://cdn.shopify.com/s/files/1/0433/5812/6245/files/chander_pahar_bengali_download.pdf
    • https://cdn.shopify.com/s/files/1/0434/0862/1719/files/abnormal_psychology_barlow_8th.pdf
    • https://cdn.shopify.com/s/files/1/0435/1423/2996/files/vonenirubesajaxuga.pdf
    • https://cdn.shopify.com/s/files/1/0438/5875/5749/files/building_design_and_drawing_book.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_off0000b139.bin
2178ab0ca83f030c97bc33e916552f21d53902fce7b1948a44c11e8025e0462f
pdf-font-stream PDF embedded font (sfnt) at offset 0xB139 5468 bytes
font_01_sfnt_off0000c3ba.bin
372d892618b7cff2bfd44d314c12cfbd73f22e62ebb92dd03f663b740531d6aa
pdf-font-stream PDF embedded font (sfnt) at offset 0xC3BA 10540 bytes