Malicious PDF — malware analysis report

Static analysis result for SHA-256 98455f77658fa8fe…

MALICIOUS

PDF

45.2 KB Created: 2020-08-15 04:46:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 19a6bd4164075618a5a271935d8b0221 SHA-1: fafaf266444913251ba202d0231656a7be34ece8 SHA-256: 98455f77658fa8fe13abf83db1432950b30e1f568925b19fd596b1186bc5142d
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 pointing to Shopify domains, but one critical link directs to a known malicious redirector. The document body, though partially corrupted, suggests a lure related to an 'introduction paragraph worksheet'. The ML classifier strongly indicated maliciousness, and the PDF structure itself is flagged for containing a mass external PDF link farm. The primary malicious IOC is the redirector URL, which likely leads to 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.cc/pify?keyword=writing+an+introduction+paragraph+worksheet
    • http://files.trrope.com/uploads/1/3/2/7/132740435/1014737.pdf
    • http://bejuluko.premieroftampabay.com/uploads/1/3/1/4/131456363/536c40b2.pdf
    • http://files.jiniepku.com/uploads/1/3/1/4/131453967/4735930.pdf
    • http://files.lingsgardenstore.com/uploads/1/3/2/7/132740234/rogivagakur.pdf
    • https://cdn.shopify.com/s/files/1/0429/6392/7206/files/zekuv.pdf
    • https://cdn.shopify.com/s/files/1/0434/0868/7269/files/fejufewamomimifewuwixuw.pdf
    • https://cdn.shopify.com/s/files/1/0433/0458/3318/files/definition_of_compressional.pdf
    • https://cdn.shopify.com/s/files/1/0440/2708/4965/files/vexodinasenarepudezawawe.pdf
    • https://cdn.shopify.com/s/files/1/0434/5597/1492/files/70802210900.pdf
    • https://cdn.shopify.com/s/files/1/0431/0922/0503/files/mavukaju.pdf
    • https://cdn.shopify.com/s/files/1/0439/9228/5342/files/free_christmas_wallpaper_hd_for_android.pdf
    • https://cdn.shopify.com/s/files/1/0427/4126/8647/files/zisuxaf.pdf
    • https://cdn.shopify.com/s/files/1/0427/9848/1564/files/mabasega.pdf
    • https://cdn.shopify.com/s/files/1/0435/4323/2661/files/21734810361.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_off00007190.bin
bce86177cfd49d586a9ce2eb99b52e5d58aa86c0c7906e51d02c86677cb08bcd
pdf-font-stream PDF embedded font (sfnt) at offset 0x7190 5472 bytes
font_01_sfnt_off00008437.bin
a4f9568705b17e858fc0f0d5fc8798d5e026d4ed75b7aabf75ccec8f7e15cad5
pdf-font-stream PDF embedded font (sfnt) at offset 0x8437 10308 bytes