Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9581882535b088d…

MALICIOUS

PDF

42.0 KB Created: 2020-08-11 22:20:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 25f6bd784b1ba65e7a40669224347d20 SHA-1: b9d7f71c985326b6c6a8056ceb8859e64e04d212 SHA-256: b9581882535b088d6f6e9415281456637ff5571fe9dd724e1f81286d7e67f5a3
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a high number of embedded links, many pointing to Shopify domains, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'outcomes intermediate second edition student's book pdf' and the malicious URL, suggesting a lure to download a malicious file disguised as an educational resource. 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.cc/wb?keyword=outcomes%20intermediate%20second%20edition%20student
    • http://files.eaststokesoutreachministry.org/uploads/1/3/1/3/131398010/28da344121.pdf
    • http://files.kholabakso.com/uploads/1/3/1/8/131871687/7cf536ae.pdf
    • http://juvowebam.procon-loe.ru/uploads/1/3/2/7/132710621/f825ba.pdf
    • https://cdn.shopify.com/s/files/1/0434/4433/8838/files/fadutovufelulevime.pdf
    • https://cdn.shopify.com/s/files/1/0435/9946/2558/files/riwobetununu.pdf
    • https://cdn.shopify.com/s/files/1/0433/3391/0681/files/old_youtube_layout.pdf
    • https://cdn.shopify.com/s/files/1/0430/5554/6517/files/23887504894.pdf
    • https://cdn.shopify.com/s/files/1/0431/0971/2021/files/sapeji.pdf
    • https://cdn.shopify.com/s/files/1/0437/5419/3047/files/72807696450.pdf
    • https://cdn.shopify.com/s/files/1/0432/5448/1056/files/73197423179.pdf
    • https://cdn.shopify.com/s/files/1/0430/3205/1873/files/xeleg.pdf
    • https://cdn.shopify.com/s/files/1/0429/2096/8358/files/adobe_illustrator_exportieren.pdf
    • https://cdn.shopify.com/s/files/1/0431/3566/4284/files/personal_pronouns_flashcards_printable.pdf
    • https://cdn.shopify.com/s/files/1/0427/5961/8716/files/jeffrey_archer_heads_you_win_download.pdf
    • https://cdn.shopify.com/s/files/1/0435/5417/7183/files/zugojigabijinodevo.pdf
    • https://cdn.shopify.com/s/files/1/0436/4576/3744/files/30876008699.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_off000065cf.bin
c5d4f70f55d372050c4076e22c18c5317ba63b016496f1c812b3619205f1fce8
pdf-font-stream PDF embedded font (sfnt) at offset 0x65CF 5532 bytes
font_01_sfnt_off00007887.bin
a7036636dbc9b5a323e24e9bfb5e195ee2cdbf5a981fcbd66a5f392fccaf49c0
pdf-font-stream PDF embedded font (sfnt) at offset 0x7887 10024 bytes