Malicious PDF — malware analysis report

Static analysis result for SHA-256 c908ba0f4f9c7d73…

MALICIOUS

PDF

39.7 KB Created: 2020-08-13 12:04:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e77bd9404f2c0407190c7ee6b2b87651 SHA-1: 15ce552d499044f600dd2518554b8d66e6abeb6c SHA-256: c908ba0f4f9c7d7392cc48c8ec4864bdd854f8255d873a6cd02be15f52427b27
154 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, including a primary malicious redirector at `https://ttraff.cc/wb?keyword=classification%20of%20bacteria%20bergey's%20manual`. This URL is likely used to deliver a secondary payload or redirect the user to a phishing site. The ML classifier strongly indicated maliciousness, and the presence of a link farm suggests an attempt to manipulate search engine results or distribute malicious links.

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/wb?keyword=classification%20of%20bacteria%20bergey
    • http://files.drydesign.co.uk/uploads/1/3/1/8/131871433/5679692.pdf
    • http://files.paulyeonlee.com/uploads/1/3/0/9/130968993/pelina.pdf
    • http://files.edinburghacupuncture.com/uploads/1/3/0/8/130814529/tanusavovog-maromojeneximo-duxafigezomu.pdf
    • http://files.emuskmedia.com/uploads/1/3/0/7/130738614/873b890a83.pdf
    • https://cdn.shopify.com/s/files/1/0435/9615/2995/files/fizivudivopu.pdf
    • https://cdn.shopify.com/s/files/1/0439/0433/6040/files/82587034802.pdf
    • https://cdn.shopify.com/s/files/1/0432/0913/0143/files/amazfit_bip_user_manual.pdf
    • https://cdn.shopify.com/s/files/1/0432/1571/6513/files/7858572551.pdf
    • https://cdn.shopify.com/s/files/1/0433/3902/2485/files/jelajolulovozug.pdf
    • https://cdn.shopify.com/s/files/1/0433/9521/9623/files/jobepu.pdf
    • https://cdn.shopify.com/s/files/1/0432/8800/2710/files/1605494865.pdf
    • https://cdn.shopify.com/s/files/1/0440/9622/5432/files/bash_on_windows.pdf
    • https://cdn.shopify.com/s/files/1/0429/1559/4399/files/aiims_assertion_reason_book_download.pdf
    • https://cdn.shopify.com/s/files/1/0430/3906/4225/files/79885741287.pdf
    • https://cdn.shopify.com/s/files/1/0431/7573/9553/files/guditoxivelifox.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_off00005de6.bin
fd2f59e82f044f08d93deb97240a0bfd22fe8241c58ebb58fad815a23ac96bb2
pdf-font-stream PDF embedded font (sfnt) at offset 0x5DE6 5384 bytes
font_01_sfnt_off0000702a.bin
e0c5d9560df73a39b867b8c8825fb37aab43e1fa8e4f641735cdc46c1f06fce6
pdf-font-stream PDF embedded font (sfnt) at offset 0x702A 9908 bytes