Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c48031d86509c2d…

MALICIOUS

PDF

44.6 KB Created: 2020-08-11 23:24:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2f3504f17e5a09c59ca43e26f65729c0 SHA-1: 40e88f0b4212f743bfdf239920a89f6df17b4081 SHA-256: 8c48031d86509c2dfb5e302b79644e3b9767fe98ecc6e445741408cf2eb84ffd
152 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous PDFs hosted on Shopify, likely as a SEO spam or content farm. One of the critical heuristic firings indicates that a link within the PDF points to known malicious redirector infrastructure, specifically 'https://ttraff.cc/pify?keyword=html+to+pdf+php+library'. This suggests the document is designed to trick users into clicking the link under the guise of a useful tool, leading them to malicious sites. The ML classifier also 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/pify?keyword=html+to+pdf+php+library
    • http://files.mrsnoacksclass.com/uploads/1/3/1/4/131437848/c3e7e08d8ea8cd.pdf
    • http://morowuki.threeatlantacats.com/uploads/1/3/0/7/130738714/rekidupatazuwepewi.pdf
    • http://fiwena.dulleslibrary.com/uploads/1/3/2/8/132814930/6727548.pdf
    • https://cdn.shopify.com/s/files/1/0428/2135/3635/files/30076816584.pdf
    • https://cdn.shopify.com/s/files/1/0433/0674/6011/files/harry_potter_book_one.pdf
    • https://cdn.shopify.com/s/files/1/0428/3134/7868/files/21441893154.pdf
    • https://cdn.shopify.com/s/files/1/0433/4000/5541/files/free_bullet_journal_printables_2020.pdf
    • https://cdn.shopify.com/s/files/1/0431/9543/3117/files/nilaboxudesawetapapekuj.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/91960476686.pdf
    • https://cdn.shopify.com/s/files/1/0436/0772/0094/files/38608212456.pdf
    • https://cdn.shopify.com/s/files/1/0431/7298/7046/files/57606680223.pdf
    • https://cdn.shopify.com/s/files/1/0436/9183/5547/files/87952160162.pdf
    • https://cdn.shopify.com/s/files/1/0428/0408/4899/files/walafubijilubalasoxeka.pdf
    • https://cdn.shopify.com/s/files/1/0435/8933/7256/files/gulenuwitatexikoke.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_off000068be.bin
e5aa745a4e9020e02f6f2951ed5c09877352ef97e6c81b75b178353acda29263
pdf-font-stream PDF embedded font (sfnt) at offset 0x68BE 5308 bytes
font_01_sfnt_off00007aa2.bin
3968807831a452486b8d3776d081a131ff966311cf39fd024bbe4d903824d85d
pdf-font-stream PDF embedded font (sfnt) at offset 0x7AA2 13756 bytes