Malicious PDF — malware analysis report

Static analysis result for SHA-256 bdeaa3226f4181b0…

MALICIOUS

PDF

38.5 KB Created: 2020-07-25 22:29:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cffa92e6cbc2a5a13e3adaaac03de407 SHA-1: a1fc7ad7c57e6af95dc2329b674add4cf3204d83 SHA-256: bdeaa3226f4181b0a25d0d352752b38ef9954975b27eef0663329261d3c263d5
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 pointing to Shopify domains, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, appears to reference academic material, suggesting a lure to disguise the malicious intent. The ML classifier strongly supports the malicious nature of this PDF.

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=ecgs+made+easy+5th+edition+answers
    • http://files.nash-style.com/uploads/1/3/1/4/131455337/694de57c.pdf
    • http://files.clubcollege-bound.com/uploads/1/3/1/4/131436997/2009637.pdf
    • http://files.threeriversautomodelers.net/uploads/1/3/0/7/130776502/34d52874e5f9a6.pdf
    • http://files.threeriversautomodelers.net/uploads/1/3/0/7/130776502/34d52874e5f9a6.pd
    • https://cdn.shopify.com/s/files/1/0432/0041/3856/files/bujidarakasaw.pdf
    • https://cdn.shopify.com/s/files/1/0437/7129/7943/files/25111171343.pdf
    • https://cdn.shopify.com/s/files/1/0432/9812/8036/files/5240942609.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/37263727017.pdf
    • https://cdn.shopify.com/s/files/1/0431/1754/3588/files/wetuwulurisusifeso.pdf
    • https://cdn.shopify.com/s/files/1/0432/7230/6846/files/55340929656.pdf
    • https://cdn.shopify.com/s/files/1/0431/5391/6053/files/vokotama.pdf
    • https://cdn.shopify.com/s/files/1/0428/4357/0343/files/61490013766.pdf
    • https://cdn.shopify.com/s/files/1/0431/3396/0341/files/tuluvab.pdf
    • https://cdn.shopify.com/s/files/1/0435/5883/0229/files/25170480005.pdf
    • https://cdn.shopify.com/s/files/1/0429/2762/0249/files/49202219053.pdf
    • https://cdn.shopify.com/s/files/1/0433/0120/8232/files/53969021903.pdf
    • https://cdn.shopify.com/s/files/1/0433/0671/3253/files/95630963478.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_off0000577d.bin
0e9b05464a73ef2229c9e86ceb232b4dadce5e3139086795777e6e789414dc55
pdf-font-stream PDF embedded font (sfnt) at offset 0x577D 5384 bytes
font_01_sfnt_off000069b9.bin
7aa7de6522783017332b649577634bde839fc8bd80083dd3b6860e0dea5d0ea7
pdf-font-stream PDF embedded font (sfnt) at offset 0x69B9 9796 bytes