Malicious PDF — malware analysis report

Static analysis result for SHA-256 90407d5350b97d60…

MALICIOUS

PDF

50.9 KB Created: 2020-07-29 14:53:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: eb29651e87b5d58b731b7c69f13c85e2 SHA-1: 5835a1e62112c4cc07393c73b2a84e211610e933 SHA-256: 90407d5350b97d60aed04bb8bbaf149e02980a220a6b584946958f3538b5c57a
154 Risk Score

Malware Insights

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

The PDF contains embedded links that redirect to known malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The ML classifier also strongly flagged this PDF as malicious. The document body, though heavily obfuscated, appears to be a lure related to 'Us army apft score chart pdf'. The presence of numerous external PDF links suggests a link farm or SEO poisoning tactic to distribute malicious content. No scripts were extracted from this sample.

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=us+army+apft+score+chart+pdf
    • http://files.leemlizzyonline.com/uploads/1/3/2/6/132681415/9360523.pdf
    • http://files.oldpathsdzingre.org/uploads/1/3/1/0/131071063/zinesemojuwi.pdf
    • http://files.sunkissedbridal.com/uploads/1/3/2/6/132683000/8829397.pdf
    • http://files.simonesoernsen.com/uploads/1/3/1/3/131383514/c9d5b8fa8.pdf
    • http://files.sunkissedbridal.com/uploads/1/3/2/
    • https://cdn.shopify.com/s/files/1/0430/3536/1442/files/zunesilinukozejoxi.pdf
    • https://cdn.shopify.com/s/files/1/0433/6176/3480/files/maxumavamijiwinixasep.pdf
    • https://cdn.shopify.com/s/files/1/0434/4017/7314/files/66999968266.pdf
    • https://cdn.shopify.com/s/files/1/0429/8578/3455/files/gejipifakovudususemel.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/46946939033.pdf
    • https://cdn.shopify.com/s/files/1/0431/5627/5362/files/maralubova.pdf
    • https://cdn.shopify.com/s/files/1/0429/1916/6105/files/suwukupobaku.pdf
    • https://cdn.shopify.com/s/files/1/0428/8688/9625/files/fidifixozerofegono.pdf
    • https://cdn.shopify.com/s/files/1/0430/9660/4825/files/93923109177.pdf
    • https://cdn.shopify.com/s/files/1/0435/8144/0168/files/56342824042.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_off0000805e.bin
3b821ed0924ed50be71bc8fda82442b1bd5ffb517bcecba7b642bc61bbd1b891
pdf-font-stream PDF embedded font (sfnt) at offset 0x805E 5092 bytes
font_01_sfnt_off000091ab.bin
a500a58750c0178f316c7fde61a87a9953bfa07d43e1ac32de5065ebd352a235
pdf-font-stream PDF embedded font (sfnt) at offset 0x91AB 14488 bytes