Malicious PDF — malware analysis report

Static analysis result for SHA-256 a6a3b033b2a19f89…

MALICIOUS

PDF

41.2 KB Created: 2020-08-10 20:22:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0900c967a8e24500077202adc5c34c36 SHA-1: 6c6dfb4c4631cd2852457a851e37c3943c6f274d SHA-256: a6a3b033b2a19f89223fd35b2036be96c0cadc23bf094949d0590d0e9c079687
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, many of which are designed to appear as legitimate documents but lead to a link farm. One of these links, 'https://ttraff.ru/pify?keyword=pdf+antropologia+social', is identified as a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body itself is heavily obfuscated and contains embedded URLs, suggesting a lure to external malicious content.

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=pdf+antropologia+social
    • http://files.joanlinnehan.com/uploads/1/3/2/8/132816096/bozurijuwuda-tebupuj-lojenoxato-tupebenederi.pdf
    • http://badiradi.agorapublications.com/uploads/1/3/0/7/130776445/saxadibezafo.pdf
    • http://files.communitychurchofkeystoneheights.org/uploads/1/3/2/3/132302872/6017342.pdf
    • https://cdn.shopify.com/s/files/1/0433/0258/4480/files/juvefeg.pdf
    • https://cdn.shopify.com/s/files/1/0431/1446/3386/files/68006850816.pdf
    • https://cdn.shopify.com/s/files/1/0431/5113/0785/files/44633086911.pdf
    • https://cdn.shopify.com/s/files/1/0431/3631/9639/files/abstract_class_in_cpp.pdf
    • https://cdn.shopify.com/s/files/1/0430/1750/2869/files/gafubibatowawuzukev.pdf
    • https://cdn.shopify.com/s/files/1/0438/6072/1829/files/58851783831.pdf
    • https://cdn.shopify.com/s/files/1/0434/2143/4005/files/29261418665.pdf
    • https://cdn.shopify.com/s/files/1/0432/2073/0011/files/saxizibodunemura.pdf
    • https://cdn.shopify.com/s/files/1/0439/1793/4747/files/33947886514.pdf
    • https://cdn.shopify.com/s/files/1/0430/8933/0325/files/romoke.pdf
    • https://cdn.shopify.com/s/files/1/0433/1179/2286/files/71765242815.pdf
    • https://cdn.shopify.com/s/files/1/0428/8266/2553/files/jitezun.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_off000063e3.bin
fa1caf869f06b0cb06278d34b801a6f1a2c4030ba77c86504a2fd2de9ff9d872
pdf-font-stream PDF embedded font (sfnt) at offset 0x63E3 5324 bytes
font_01_sfnt_off00007609.bin
f161b96dcfd9fc8fb4b932b4f8cd7077755409ac276c0a43657f5e31eff3b8cd
pdf-font-stream PDF embedded font (sfnt) at offset 0x7609 9924 bytes