Malicious PDF — malware analysis report

Static analysis result for SHA-256 ec159c463de44d88…

MALICIOUS

PDF

36.9 KB Created: 2020-08-22 12:19:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f177abaf0d927a200384c6853171957a SHA-1: ae805b29269fa94b58b3b7f5c6dcbab5dc600ed9 SHA-256: ec159c463de44d8886eb0ae6c9d51aad018cb01855792bfd5fdd69ae6e33b259
152 Risk Score

Malware Insights

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

The PDF contains numerous links, including one pointing to a known malicious redirector (ttraff.ru). The document body, though heavily obfuscated, contains text suggesting it is a 'Speech punctuation worksheet year 3', which is likely a lure. The presence of multiple PDF links, many hosted on Shopify, suggests a link farm or SEO poisoning tactic to distribute malicious content. The ML classifier also strongly indicated maliciousness.

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=speech+punctuation+worksheet+year+3
    • http://fitugoki.allie-coosh.com/uploads/1/3/2/6/132680813/pufanol.pdf
    • http://files.top-value.com/uploads/1/3/1/1/131163737/e4ee340ed21.pdf
    • http://ginonako.tabiatbeladiest.com/uploads/1/3/1/6/131606349/jetozemu_pidobovopatu.pdf
    • https://cdn.shopify.com/s/files/1/0429/1022/0447/files/59339169422.pdf
    • https://cdn.shopify.com/s/files/1/0432/7338/8190/files/jutunawovuwimopo.pdf
    • https://cdn.shopify.com/s/files/1/0440/5598/6341/files/reraxojiguji.pdf
    • https://cdn.shopify.com/s/files/1/0433/6409/0006/files/23479001387.pdf
    • https://cdn.shopify.com/s/files/1/0430/4430/7098/files/voxuterutevulifajimudexe.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/75904593322.pdf
    • https://cdn.shopify.com/s/files/1/0437/5108/0087/files/affective_domain_objectives.pdf
    • https://cdn.shopify.com/s/files/1/0434/7641/8722/files/17655920541.pdf
    • https://cdn.shopify.com/s/files/1/0433/0297/7700/files/jirifozixelenategis.pdf
    • https://cdn.shopify.com/s/files/1/0429/5622/6716/files/uninstall_citrix_receiver_mac.pdf
    • https://cdn.shopify.com/s/files/1/0440/8524/8165/files/fejil.pdf
    • https://cdn.shopify.com/s/files/1/0433/4039/8750/files/zufironanexover.pdf
    • https://cdn.shopify.com/s/files/1/0430/1615/9395/files/59478851435.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_off000051f4.bin
8fce85ddee65bd47527992546bcee490713d5d5e777978aa3f17554efd2e477b
pdf-font-stream PDF embedded font (sfnt) at offset 0x51F4 5516 bytes
font_01_sfnt_off000064c2.bin
0ca3108ad009372f4a0ed778047c38a558c603fb76c04e60e73fed19c3206e41
pdf-font-stream PDF embedded font (sfnt) at offset 0x64C2 9984 bytes