Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab20527bc6897b88…

MALICIOUS

PDF

49.9 KB Created: 2020-07-24 22:16:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 17c95dce5bdfdf913faec011a603ee71 SHA-1: 53b3b37bce56e46b746332aa777d44a1fe02cf69 SHA-256: ab20527bc6897b884c50c0f80679bce267f52d88e817db35474a7511350945b2
152 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by a machine learning classifier and contains numerous embedded links. One critical heuristic identified a link to a known malicious redirector, and another noted a large farm of external PDF links, many hosted on Shopify. The document body, though heavily obfuscated, contains text related to 'Ethiopian agro-ecological zones pdf' and the wkhtmltopdf tool, suggesting a lure document. The primary attack pattern involves redirecting users to malicious infrastructure via these 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/pify?keyword=ethiopian+agro-+ecological+zones+pdf
    • http://files.treetogrow.com/uploads/1/3/0/9/130969051/gibomakimeledata.pdf
    • http://files.carolwolfeclaydesign.com/uploads/1/3/0/7/130738875/8748366.pdf
    • http://files.activatorsociety.org/uploads/1/3/1/1/131164032/6834136.pdf
    • http://files.bluenosewoodworks.com/uploads/1/3/2/8/132815961/somokirolurujewikusi.pdf
    • https://cdn.shopify.com/s/files/1/0433/0808/9509/files/55643442385.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/dipudakafadaned.pdf
    • https://cdn.shopify.com/s/files/1/0429/6241/9863/files/70108318888.pdf
    • https://cdn.shopify.com/s/files/1/0428/0962/2691/files/fasagarezaluma.pdf
    • https://cdn.shopify.com/s/files/1/0431/5725/8401/files/81051259250.pdf
    • https://cdn.shopify.com/s/files/1/0432/6214/8763/files/palefuwugunazumilevali.pdf
    • https://cdn.shopify.com/s/files/1/0431/4133/3147/files/58377099601.pdf
    • https://cdn.shopify.com/s/files/1/0435/5771/6117/files/99721940526.pdf
    • https://cdn.shopify.com/s/files/1/0429/7667/3946/files/kifukajalameji.pdf
    • https://cdn.shopify.com/s/files/1/0433/1054/7099/files/31952756648.pdf
    • https://cdn.shopify.com/s/files/1/0434/3952/1959/files/vofufovom.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_off000085a0.bin
f2478fd2daf697820fd222652e7a8b0196c7400f9691ff600602a44b40f4c720
pdf-font-stream PDF embedded font (sfnt) at offset 0x85A0 5244 bytes
font_01_sfnt_off00009777.bin
b2525ef81ace03db92c3dffb3540bd54eb4c7c37c8367f970b9a203588799c9b
pdf-font-stream PDF embedded font (sfnt) at offset 0x9777 10088 bytes