Malicious PDF — malware analysis report

Static analysis result for SHA-256 af1bef646ea038e3…

MALICIOUS

PDF

33.3 KB Created: 2020-08-19 17:01:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1372afdd2c84f36b249870e11ebc07d0 SHA-1: 3ed95ef17b3a8e64eb4a3a89cfd39e29038d02c3 SHA-256: af1bef646ea038e3692a0185638aa103ffe60b03354f857356b0d4b9ded4c132
152 Risk Score

Malware Insights

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

The PDF contains a link disguised as a worksheet, which redirects to a known malicious redirector. The PDF also hosts a large number of external links, many pointing to Shopify, suggesting a link farm or SEO abuse tactic. The ML classifier strongly indicated maliciousness. The primary malicious IOC is the redirector URL.

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=predicate+adjective+worksheet+6th+grade
    • http://files.wallsofwondersaddlebrooke.com/uploads/1/3/1/3/131380467/41856e48f4713.pdf
    • http://files.highpeaksadventureco.com/uploads/1/3/0/8/130874009/torifefar.pdf
    • http://files.farmpedals.com/uploads/1/3/2/6/132682076/cda7935315c.pdf
    • https://cdn.shopify.com/s/files/1/0437/0766/2504/files/the_roman_catholic_bible.pdf
    • https://cdn.shopify.com/s/files/1/0429/1615/1455/files/pesinotomamufelewi.pdf
    • https://cdn.shopify.com/s/files/1/0435/9582/5314/files/dewur.pdf
    • https://cdn.shopify.com/s/files/1/0435/3730/1653/files/ppt_to_jpg.pdf
    • https://cdn.shopify.com/s/files/1/0433/4970/4854/files/15595219041.pdf
    • https://cdn.shopify.com/s/files/1/0437/0530/3205/files/56546036681.pdf
    • https://cdn.shopify.com/s/files/1/0439/2543/8619/files/bsc_1st_year_maths_book_solution.pdf
    • https://cdn.shopify.com/s/files/1/0430/5590/6967/files/savogewevuwu.pdf
    • https://cdn.shopify.com/s/files/1/0432/6899/7286/files/nutajudipemisikuj.pdf
    • https://cdn.shopify.com/s/files/1/0427/8665/2316/files/2402701829.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_off00004457.bin
cad8423299a3398c4017ebca1d49de486b0e62f53cf3c1fae2101d2a80402a7a
pdf-font-stream PDF embedded font (sfnt) at offset 0x4457 5616 bytes
font_01_sfnt_off0000577e.bin
84deee3425f28490602167fb3b8165f454aee216e2001d4fe25ecc1f44583b6a
pdf-font-stream PDF embedded font (sfnt) at offset 0x577E 9648 bytes