Malicious PDF — malware analysis report

Static analysis result for SHA-256 b4bac7d00860723f…

MALICIOUS

PDF

42.5 KB Created: 2020-07-30 16:26:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2b8130512ff88db3466a6446400e81bd SHA-1: 9d6dabb3b66a43e65d8926d4bedf20fa3fe13060 SHA-256: b4bac7d00860723f3c00c90bb02c93c13cbc63e83fff9491c52436be95c26bde
154 Risk Score

Malware Insights

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

The PDF contains multiple embedded links, with one identified as a malicious redirector. The ML classifier strongly indicates maliciousness. The document body appears to be obfuscated or corrupted, but the presence of the malicious redirector URL suggests an attempt to lure the user to a harmful site. The PDF_SEO_LINK_FARM heuristic indicates a large number of outbound links, further supporting a malicious intent.

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=citalopram+davis+pdf
    • http://files.lushgardenhotels.com/uploads/1/3/2/6/132683121/jubinunu.pdf
    • http://files.grundmeyerleadersearch.com/uploads/1/3/1/6/131636990/sifixoj_jutixepipi_bevasagipaxuja_sivosukisozi.pdf
    • http://files.aestern.org/uploads/1/3/1/3/131381614/0b6fa851bbca669.pdf
    • http://files.virginianaildesignsllc.com/uploads/1/3/2/6/132695339/zobugumato.pdf
    • http://files.virginianaildesignsllc.com/uploads/1/3/2/6/132695339/z
    • https://cdn.shopify.com/s/files/1/0429/3846/6467/files/21237809437.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/47878122177.pdf
    • https://cdn.shopify.com/s/files/1/0435/2730/7416/files/sagugemixikula.pdf
    • https://cdn.shopify.com/s/files/1/0437/7152/7330/files/92401747694.pdf
    • https://cdn.shopify.com/s/files/1/0437/5573/3153/files/fazojulogugozolokeragojix.pdf
    • https://cdn.shopify.com/s/files/1/0430/0147/9321/files/74537720352.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/67279733654.pdf
    • https://cdn.shopify.com/s/files/1/0437/4275/7029/files/puvikojulimixopusenez.pdf
    • https://cdn.shopify.com/s/files/1/0429/4580/6503/files/12160889652.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/lozafawofife.pdf
    • https://cdn.shopify.com/s/files/1/0431/2013/2257/files/72886022931.pdf
    • https://cdn.shopify.com/s/files/1/0433/1077/6478/files/zunilomuwodumoribizixip.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_off00006aff.bin
6783fade2ca6eb228aaec6d240ac8ae74725452d4c15acfd568dbfeb7aa788ab
pdf-font-stream PDF embedded font (sfnt) at offset 0x6AFF 4832 bytes
font_01_sfnt_off00007b71.bin
fceee9c95f45db68a5d452387110425d4cf936587b9f271fe479952b376e378c
pdf-font-stream PDF embedded font (sfnt) at offset 0x7B71 9880 bytes