Malicious PDF — malware analysis report

Static analysis result for SHA-256 72cd4a20e3ac2eb1…

MALICIOUS

PDF

35.3 KB Created: 2020-08-03 18:50:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 931a8a8427e11c874c5e3720c1f234fc SHA-1: 4deab866d6cebb1b416936443d394036e2df6893 SHA-256: 72cd4a20e3ac2eb1fb1f65c92869ace30758f25d92750c0d06fab0bcb167eebe
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of external links, many of which point to a redirector service. The document body text, though partially garbled, suggests a lure related to a textbook chapter, likely to entice clicks on the malicious link. The ML classifier strongly indicated maliciousness, and the PDF structure itself was flagged for containing a 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.cc/pify?keyword=ways+of+the+world+textbook+pdf+chapter+23
    • http://files.juliannawells.com/uploads/1/3/1/6/131637881/9550118.pdf
    • http://vugotikad.seekanddestroy.info/uploads/1/3/0/8/130814058/zujow.pdf
    • http://files.georgiamartinteachingportfolio.com/uploads/1/3/2/3/132303219/zesujejabeno.pdf
    • http://files.mdyc.com/uploads/1/3/1/3/131381518/xomajesugatomipadov.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/38461358607.pdf
    • https://cdn.shopify.com/s/files/1/0428/8839/6959/files/52414843217.pdf
    • https://cdn.shopify.com/s/files/1/0434/7727/0692/files/30557735100.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/pewobaropelizovijekozuji.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/61047377128.pdf
    • https://cdn.shopify.com/s/files/1/0435/2265/4362/files/83654913578.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/46287179129.pdf
    • https://cdn.shopify.com/s/files/1/0430/8277/6729/files/mulimiwawa.pdf
    • https://cdn.shopify.com/s/files/1/0427/5775/0951/files/35650174199.pdf
    • https://cdn.shopify.com/s/files/1/0429/3397/7247/files/zasejaguj.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_off000044e4.bin
e30a43b06b0b5c0f3c9db887c27eb448b213ccbff36b48f0ba22a132c9183708
pdf-font-stream PDF embedded font (sfnt) at offset 0x44E4 6020 bytes
font_01_sfnt_off0000597c.bin
4cbfc0a73680349112e7ffba669ca760d4c2567559f89b89600fcbc236c6845e
pdf-font-stream PDF embedded font (sfnt) at offset 0x597C 11324 bytes