Malicious PDF — malware analysis report

Static analysis result for SHA-256 a68db8abafd67954…

MALICIOUS

PDF

42.2 KB Created: 2020-08-10 05:22:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ed812dd2635370f76ed4adb02c737a81 SHA-1: 0e2ff0c371ea1a9904225dfa4aff411c0eb3d32c SHA-256: a68db8abafd679545f57a2ef9a4a646c01f75c805a17b0427d44a296211a4c1d
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, many of which point to a redirector service (ttraff.ru) that is known to host malicious content. The document body, though heavily obfuscated, contains the same redirector URL and appears to be a lure for a free PDF download. The ML classifier strongly indicates maliciousness, and the PDF_MALICIOUS_REDIRECTOR_LINK heuristic confirms the presence of a malicious redirector.

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=oxford+picture+dictionary+english+french+pdf+free+download
    • http://files.earldthomas.org/uploads/1/3/0/9/130969182/tasivafubad.pdf
    • http://files.gpannualconference.com/uploads/1/3/2/3/132303117/2188665.pdf
    • http://files.uclacogsci.com/uploads/1/3/1/4/131483830/4319248.pdf
    • http://lewinav.jurneyvetneuro.com/uploads/1/3/1/1/131164250/b013f608bda95ab.pdf
    • https://cdn.shopify.com/s/files/1/0432/8423/4398/files/4770525635.pdf
    • https://cdn.shopify.com/s/files/1/0436/3229/6089/files/fajivumanozuzejeletovugi.pdf
    • https://cdn.shopify.com/s/files/1/0433/3967/7855/files/sivabupaxubawi.pdf
    • https://cdn.shopify.com/s/files/1/0437/2280/1306/files/more_agile_testing_book.pdf
    • https://cdn.shopify.com/s/files/1/0429/7916/4314/files/abecedario_completo_mayusculas_y_minusculas.pdf
    • https://cdn.shopify.com/s/files/1/0435/7016/7966/files/13757219816.pdf
    • https://cdn.shopify.com/s/files/1/0430/2825/0781/files/zewifeju.pdf
    • https://cdn.shopify.com/s/files/1/0432/0270/7616/files/97509692452.pdf
    • https://cdn.shopify.com/s/files/1/0440/3747/2421/files/67724688691.pdf
    • https://cdn.shopify.com/s/files/1/0434/0888/3870/files/26682614595.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_off0000643b.bin
9a5da8236deb14164ebcb8b87f042550feba015e2ffc088a5d64e250988ec76d
pdf-font-stream PDF embedded font (sfnt) at offset 0x643B 5704 bytes
font_01_sfnt_off000077b8.bin
a7f2ec153d7a98ce9a5696d4ce8b19952bc23bacba3d64504d24dcaf6882e384
pdf-font-stream PDF embedded font (sfnt) at offset 0x77B8 10468 bytes