Malicious PDF — malware analysis report

Static analysis result for SHA-256 ab8503e93f365ea4…

MALICIOUS

PDF

43.1 KB Created: 2020-08-24 03:10:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 30ff8957ddaae5a77fc5a40346ced1a9 SHA-1: dc3082f0e36530888c65d7777ae883269013ea0c SHA-256: ab8503e93f365ea41da2d8d6c539e81c2eba8cd45219097b3f3e0f90af2971c9
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with a critical heuristic firing indicating a link to known malicious redirector infrastructure. The ML classifier also strongly flagged this PDF as malicious. The primary malicious IOC is the redirector URL, which likely leads to a further stage of the attack. The document body contains metadata that appears to be obfuscated or corrupted.

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.com/pify?keyword=acrobat+amtlib.+dll
    • http://files.forcebrewery.com/uploads/1/3/2/6/132695200/5bb2eb6533fe68d.pdf
    • http://files.deborahmilesdesign.co.uk/uploads/1/3/2/8/132815054/kikufavosapa_wumidodeje_mitulu_nikaluwexur.pdf
    • http://paxajet.oxfordstation.pl/uploads/1/3/0/8/130814328/98556.pdf
    • http://files.malawiecosolutions.com/uploads/1/3/1/4/131408170/1605936.pdf
    • https://cdn.shopify.com/s/files/1/0430/3316/5986/files/76752722972.pdf
    • https://cdn.shopify.com/s/files/1/0463/2461/3275/files/biographical_data_template.pdf
    • https://cdn.shopify.com/s/files/1/0437/7244/4823/files/gujovakevowin.pdf
    • https://cdn.shopify.com/s/files/1/0435/6807/0815/files/manipulative_psychology_101.pdf
    • https://cdn.shopify.com/s/files/1/0431/6758/0322/files/88448197876.pdf
    • https://cdn.shopify.com/s/files/1/0431/6728/5408/files/bulozimodijovomujuj.pdf
    • https://cdn.shopify.com/s/files/1/0427/9461/4940/files/siwes_report_on_computer_maintenance.pdf
    • https://cdn.shopify.com/s/files/1/0430/9906/2426/files/ctet_2020_syllabus_download.pdf
    • https://cdn.shopify.com/s/files/1/0432/0998/2107/files/23672320043.pdf
    • https://cdn.shopify.com/s/files/1/0430/3113/4365/files/fevupade.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_off0000653d.bin
6f230dfbd4c15c9e16a3dea175ef8eb643d06464c8b2aba9d465d911df4d42fc
pdf-font-stream PDF embedded font (sfnt) at offset 0x653D 5068 bytes
font_01_sfnt_off00007658.bin
d949c8ece70fa1bd17a15f60374fa8354ec6a27a8e1770a0d9ddf0aa7c6b47f2
pdf-font-stream PDF embedded font (sfnt) at offset 0x7658 13100 bytes