Malicious PDF — malware analysis report

Static analysis result for SHA-256 da9db6ee749abe27…

MALICIOUS

PDF

47.9 KB Created: 2020-08-01 22:25:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 237c49ff813348ab0b08c06f8dcaa0a1 SHA-1: 9692357df8c708272175e9d0e252c1c1dc264852 SHA-256: da9db6ee749abe27becda6be8b43f517f1e5043884b2f811b30a7321365b756b
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of embedded links, with one specifically identified as a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body text, though partially garbled, contains the suspicious URL and references to 'discord.js cpu usage', suggesting a lure or phishing attempt. 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=discord.+js+cpu+usage
    • http://files.dylanness.com/uploads/1/3/0/9/130969819/860cb.pdf
    • http://files.cvilletrackclub.org/uploads/1/3/1/8/131859895/nibixadisoligu_mozojuton_wifutugozixe.pdf
    • http://files.solonsnowhawks.org/uploads/1/3/1/4/131411539/zidululanomok-bidegipinaron-silelo-redutavinusane.pdf
    • https://cdn.shopify.com/s/files/1/0434/6635/8934/files/76785052029.pdf
    • https://cdn.shopify.com/s/files/1/0430/4509/3533/files/pajiwik.pdf
    • https://cdn.shopify.com/s/files/1/0434/1107/9317/files/96011027399.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/11085861466.pdf
    • https://cdn.shopify.com/s/files/1/0433/8129/3221/files/60179978480.pdf
    • https://cdn.shopify.com/s/files/1/0435/2750/4024/files/xufev.pdf
    • https://cdn.shopify.com/s/files/1/0431/2711/1841/files/74072948947.pdf
    • https://cdn.shopify.com/s/files/1/0430/9378/6791/files/94689789609.pdf
    • https://cdn.shopify.com/s/files/1/0432/5244/9444/files/nodotisukagiverijipu.pdf
    • https://cdn.shopify.com/s/files/1/0439/6898/7294/files/consumer_reports_buying_guide_2017.pdf
    • https://cdn.shopify.com/s/files/1/0428/6221/5324/files/vanijer.pdf
    • https://cdn.shopify.com/s/files/1/0429/8211/3433/files/15862575271.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_off00007d08.bin
70c147d9246fa4255121e2e4b9e28fb2bd81beb95fd94bbf1db3ca03eaa53d1e
pdf-font-stream PDF embedded font (sfnt) at offset 0x7D08 5316 bytes
font_01_sfnt_off00008f3b.bin
5cf7a670db7d7a5cebdc983cb508bb3fec1569c5265e38ff9044ceb4f9c1dabd
pdf-font-stream PDF embedded font (sfnt) at offset 0x8F3B 10468 bytes