Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b1c0fe5aec55d59…

MALICIOUS

PDF

40.4 KB Created: 2020-08-20 05:03:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d493031c22f25de8cbc19fbc9503e732 SHA-1: a68899e5eaf1ce427a61d002d5cc61791db8900d SHA-256: 8b1c0fe5aec55d5925add7b81ca3350daa4bac255c68b9c801ade68394e351b6
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 a significant number of embedded links. One of these links, 'https://ttraff.ru/pify?keyword=complete+university+guide+2018+chemistry', points to a known malicious redirector. The document body, though heavily obfuscated, also contains this URL and numerous other links to PDF files hosted on various domains, suggesting a link farm or distribution mechanism for further 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=complete+university+guide+2018+chemistry
    • http://files.thedvguys.com/uploads/1/3/2/7/132712545/4433975.pdf
    • http://files.plaincommunitychurch.org/uploads/1/3/1/4/131453718/2518945.pdf
    • http://webug.vision-collective.com/uploads/1/3/1/3/131381204/9082cf89cd215e9.pdf
    • http://files.katherinechwazik.com/uploads/1/3/2/6/132695248/5554008.pdf
    • http://files.northwesternartreview.com/uploads/1/3/1/8/131871921/7456377.pdf
    • https://cdn.shopify.com/s/files/1/0429/6222/3263/files/ripaka.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/tevedizulav.pdf
    • https://cdn.shopify.com/s/files/1/0428/7509/3159/files/82580060739.pdf
    • https://cdn.shopify.com/s/files/1/0433/0491/1006/files/blue_eyed_cass.pdf
    • https://cdn.shopify.com/s/files/1/0430/5072/9621/files/17681210308.pdf
    • https://cdn.shopify.com/s/files/1/0440/5025/1941/files/tijosogagefoze.pdf
    • https://cdn.shopify.com/s/files/1/0429/4826/4089/files/56661036639.pdf
    • https://cdn.shopify.com/s/files/1/0431/6410/6909/files/62704822426.pdf
    • https://cdn.shopify.com/s/files/1/0437/3653/1095/files/bharat_movie_song_slow_motion_pagalworld.pdf
    • https://cdn.shopify.com/s/files/1/0438/6160/6565/files/43550277740.pdf
    • https://cdn.shopify.com/s/files/1/0434/0521/3847/files/bio_poem_format_7th_grade.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_off00005e3f.bin
b0dc760682a29a71e161cc6c6c9b7c0dcaf62acc20e655144a38a7ba0666b5b6
pdf-font-stream PDF embedded font (sfnt) at offset 0x5E3F 5864 bytes
font_01_sfnt_off00007221.bin
7a58ce94b5c9aa33e2d00f506554e448256fc05d6b3fd069cf43bca2da77b1ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x7221 10076 bytes