Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6c8b45240c45f67…

MALICIOUS

PDF

40.7 KB Created: 2020-08-22 12:55:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e66b1fce33edffb41f5dfff6f0756fec SHA-1: 87e3f5e49b8d2702e054cc1a7cb223bb49eec29e SHA-256: b6c8b45240c45f679296819f435ea40d66290db49a61caf9cd384cc80d7488ec
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.cc, disguised as a document about Achilles tendonitis exercises. The ML classifier strongly indicated maliciousness. The document body, though heavily obfuscated, contains the malicious URL and appears to be generated by wkhtmltopdf, a tool often used to create malicious PDFs. The presence of numerous Shopify-hosted links, some confirmed benign and others unknown, suggests a link farm or SEO poisoning tactic to obscure the primary malicious destination.

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=achilles+tendonitis+exercises+pdf
    • http://files.catsmeowsalon.com/uploads/1/3/0/7/130775506/ziketuvokuwojexuzij.pdf
    • http://tadimeze.pinchaschemsite.com/uploads/1/3/1/4/131482822/xoberoxawizisexag.pdf
    • https://cdn.shopify.com/s/files/1/0433/1608/4891/files/positron_annihilation.pdf
    • https://cdn.shopify.com/s/files/1/0429/4865/7318/files/bejatogofilemupididuxawen.pdf
    • https://cdn.shopify.com/s/files/1/0428/7194/7430/files/automatic_door_opening_using_pir_sensor.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/kemulubu.pdf
    • https://cdn.shopify.com/s/files/1/0433/5170/3706/files/income_support_number_report_changes.pdf
    • https://cdn.shopify.com/s/files/1/0432/0316/6369/files/29923827871.pdf
    • https://cdn.shopify.com/s/files/1/0432/7912/2587/files/voferoxomafenef.pdf
    • https://cdn.shopify.com/s/files/1/0433/8502/8758/files/74839596983.pdf
    • https://cdn.shopify.com/s/files/1/0434/5449/6935/files/nisapanelofojawelutupab.pdf
    • https://cdn.shopify.com/s/files/1/0435/8638/8136/files/84082548587.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_off0000627e.bin
f7c1ff5c03efcf2b174e0c583f0d46d54d3a727a336a61b0f044d7dfe0f3d7dd
pdf-font-stream PDF embedded font (sfnt) at offset 0x627E 5088 bytes
font_01_sfnt_off000073c2.bin
510d819882bb223787de64a5926e2fd8444a2fb5dea18f9cfe000483505da1ce
pdf-font-stream PDF embedded font (sfnt) at offset 0x73C2 10120 bytes