Malicious PDF — malware analysis report

Static analysis result for SHA-256 f4d65ab444c0814a…

MALICIOUS

PDF

40.0 KB Created: 2020-08-23 17:02:58 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f63a7815b58eae57072771d1f886914b SHA-1: f618035b3fad26e7d594c743aea973962d34a0e5 SHA-256: f4d65ab444c0814a7655fc0b542566c8e2a676936edaba082b5ed09fad0baedd
152 Risk Score

Malware Insights

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

The PDF contains a critical heuristic firing for a malicious redirector link pointing to 'ttraff.com'. The document body, though heavily obfuscated, contains text related to 'brain teaser worksheets' and the malicious URL, suggesting a social engineering lure. The PDF also exhibits characteristics of a link farm, with numerous embedded links to external PDF files, many hosted on Shopify. The ML classifier strongly flagged this PDF as malicious.

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.com/pify?keyword=brain+teaser+worksheets
    • http://files.jeepinforjesus.com/uploads/1/3/1/3/131382217/vobesuvamituz.pdf
    • http://files.karlielucas.com/uploads/1/3/0/8/130873921/1936102.pdf
    • http://sodorutej.coastalacad.com/uploads/1/3/0/7/130776394/tuxawisepevabupilo.pdf
    • https://cdn.shopify.com/s/files/1/0439/2199/7979/files/navodaya_online_form.pdf
    • https://cdn.shopify.com/s/files/1/0433/3391/0681/files/fly_sheet_clearance.pdf
    • https://cdn.shopify.com/s/files/1/0429/7293/8399/files/wifesud.pdf
    • https://cdn.shopify.com/s/files/1/0432/9517/8902/files/76440017012.pdf
    • https://cdn.shopify.com/s/files/1/0428/8466/1414/files/discord_webhooks_tutorial.pdf
    • https://cdn.shopify.com/s/files/1/0434/4460/0999/files/organic_chem_lab_survival_manual.pdf
    • https://cdn.shopify.com/s/files/1/0429/2263/9527/files/29530059014.pdf
    • https://cdn.shopify.com/s/files/1/0427/5296/6812/files/vutokovabanaxifanuw.pdf
    • https://cdn.shopify.com/s/files/1/0437/7139/6257/files/zaliwupudasa.pdf
    • https://cdn.shopify.com/s/files/1/0435/5984/6051/files/aci_sp_4.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_off00006057.bin
bdce1047de51c1af9f6bec1fc5f5eb3aaa49cd55b72a05de33bd65e426028fde
pdf-font-stream PDF embedded font (sfnt) at offset 0x6057 4948 bytes
font_01_sfnt_off00007135.bin
2256b4df3d078a0fc03364149c0b047e72c6337d10b9bad2d2991e4501cb4fa0
pdf-font-stream PDF embedded font (sfnt) at offset 0x7135 10060 bytes