Malicious PDF — malware analysis report

Static analysis result for SHA-256 682fcf40c1476407…

MALICIOUS

PDF

33.1 KB Created: 2020-08-09 08:50:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 40ab1d2aac9a4afc03d528955436e18f SHA-1: 713e9a78c13bfb07b726dc6620b074ee4f6335d7 SHA-256: 682fcf40c147640766c8908675d4690ed7caf9875e627fea6c3b30f8c04cb298
154 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic identifying a link to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains URLs that are part of a link farm, suggesting an attempt to manipulate search engine results or distribute malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the conclusion that it is used for malicious redirection.

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=capitalization+of+proper+nouns+worksheet+pdf
    • http://files.nkfanexperience.com/uploads/1/3/2/7/132710601/6209072.pdf
    • http://files.okmerica.com/uploads/1/3/1/4/131437139/a101611bd37e43a.pdf
    • http://files.wordsoundguide.com/uploads/1/3/0/7/130776809/rutifinuzepewe-juwogofo.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0441/0929/9864/files/yesu_asante_sana.pdf
    • https://cdn.shopify.com/s/files/1/0430/7818/9205/files/suveni.pdf
    • https://cdn.shopify.com/s/files/1/0427/7207/0556/files/43189278788.pdf
    • https://cdn.shopify.com/s/files/1/0427/4244/8295/files/robujoluromixofi.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/fatexuxutul.pdf
    • https://cdn.shopify.com/s/files/1/0432/3531/1775/files/30565050945.pdf
    • https://cdn.shopify.com/s/files/1/0430/6819/4978/files/70043037447.pdf
    • https://cdn.shopify.com/s/files/1/0432/8993/6025/files/34998514542.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/57189589950.pdf
    • https://cdn.shopify.com/s/files/1/0429/6749/8911/files/tepojoduzijelaxef.pdf
    • https://cdn.shopify.com/s/files/1/0433/1202/1662/files/old_king_s_great_hammer.pdf
    • https://cdn.shopify.com/s/files/1/0440/5847/6694/files/f5_on_mac.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_off00004418.bin
20796054547e4a583efc8a17b369949178fc98f97beedeeb7a0ce6e7ebcbcd5e
pdf-font-stream PDF embedded font (sfnt) at offset 0x4418 5240 bytes
font_01_sfnt_off000055fa.bin
65eb8992437f7fadbaa1b429c6396d0abe81176247fb565190ff2f14497ec86d
pdf-font-stream PDF embedded font (sfnt) at offset 0x55FA 9792 bytes