Malicious PDF — malware analysis report

Static analysis result for SHA-256 35c3a0f8ef415bca…

MALICIOUS

PDF

114.8 KB Created: 2020-08-12 10:55:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fdc690ac1898aecba47a71e0d98a73c5 SHA-1: b91c3c5b8f02e56ac25d9651d1d008ae983cfaf4 SHA-256: 35c3a0f8ef415bca7d613fa996de5d921da54ac801309088e6921d99f7664882
152 Risk Score

Malware Insights

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

The PDF is flagged as malicious by a machine learning classifier and contains embedded links. One link points to a known malicious redirector, and another is part of a large link farm designed to distribute numerous PDFs. The document body, though heavily obfuscated, contains keywords related to manuals and the malicious URL, suggesting a lure to trick users into clicking the 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.ru/pify?keyword=altivar+312+manual+portugues+pdf
    • http://files.stclementofstamford.com/uploads/1/3/1/0/131070457/8028559.pdf
    • http://nomis.soniabarneydesign.com/uploads/1/3/2/6/132681670/5362dcf2b890f12.pdf
    • http://files.webaggedit.com/uploads/1/3/1/4/131452935/b3bf31.pdf
    • https://cdn.shopify.com/s/files/1/0437/4305/1937/files/limowadamafuwakedolovovam.pdf
    • https://cdn.shopify.com/s/files/1/0431/9143/5422/files/20759848919.pdf
    • https://cdn.shopify.com/s/files/1/0429/7805/0201/files/mezijapipoloxigujorop.pdf
    • https://cdn.shopify.com/s/files/1/0434/3991/5175/files/97666732110.pdf
    • https://cdn.shopify.com/s/files/1/0435/2756/9576/files/28993450647.pdf
    • https://cdn.shopify.com/s/files/1/0431/1810/0637/files/castellated_beam_pdf.pdf
    • https://cdn.shopify.com/s/files/1/0436/1653/4685/files/xazeregagitapaj.pdf
    • https://cdn.shopify.com/s/files/1/0434/0567/2597/files/attachment_recommendation_letter.pdf
    • https://cdn.shopify.com/s/files/1/0431/5591/4918/files/bread_recipe_book_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0428/8797/0975/files/nixez.pdf
    • https://cdn.shopify.com/s/files/1/0433/6268/0984/files/zujokusanorekodufik.pdf
    • https://cdn.shopify.com/s/files/1/0432/7155/3189/files/74499622341.pdf
    • https://cdn.shopify.com/s/files/1/0433/1238/2117/files/4964151516.pdf
    • https://cdn.shopify.com/s/files/1/0431/5820/8672/files/6076802046.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_off00017124.bin
0b5681233644b71aaebb8033c6f75ed8f791c3a1efd9d88b65f1260739da6bd8
pdf-font-stream PDF embedded font (sfnt) at offset 0x17124 5756 bytes
font_01_sfnt_off000184a4.bin
ef8c736c5c6f1d2961538b7d761088b083c93f8bc59ff241dec4a1ff1be2af7f
pdf-font-stream PDF embedded font (sfnt) at offset 0x184A4 19164 bytes