Malicious PDF — malware analysis report

Static analysis result for SHA-256 84a506112e98eb57…

MALICIOUS

PDF

33.9 KB Created: 2020-09-10 19:51:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: a5ddbe98aec45e4dd499eefb90fad7fa SHA-1: 36d4239f297491a7063bbb7490da9d3c7b8c42e7 SHA-256: 84a506112e98eb57f8860a21ba63c91a77a78a150867e0ba2ce9bd190b7677a0
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a large number of embedded links, identified as a link farm, with a critical heuristic firing for linking to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains a URL that appears to be the primary malicious destination. The ML classifier also strongly indicated maliciousness. No scripts were extracted, but the presence of numerous links suggests an attempt to redirect users to potentially harmful 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.link/pify?keyword=los+cadetes+de+linares+corridos+mix
    • http://xabet.crescentboatclub.com/uploads/1/3/1/3/131381006/a45076e.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/ade4e6_0960fdbe18f34804891c648d140ea955.pdf
    • https://static.usrfiles.com/ugd/4cfbbd_8aa750dad3714f82922c0cf9c52bade7.pdf
    • https://static.usrfiles.com/ugd/2dbf5a_f75d9b44358f4d33811e7519daa34a5a.pdf
    • https://static.usrfiles.com/ugd/41a0b6_49f497350eb44700a3110d2cd408ea0e.pdf
    • https://cdn.shopify.com/s/files/1/0432/1368/4891/files/set_tbl_activesheet._listobjects_table1.pdf
    • https://cdn.shopify.com/s/files/1/0437/6572/7384/files/skf_bearing_number_catalogue.pdf
    • https://cdn.shopify.com/s/files/1/0429/3056/9382/files/23903809634.pdf
    • https://static.usrfiles.com/ugd/338562_d3244a8a5a69487abaa075a814201993.pdf
    • https://static.usrfiles.com/ugd/ed64d2_253ef0ee93284f969e2b2277f1fe647e.pdf
    • https://static.usrfiles.com/ugd/a43ec6_f1b0d2b1107b4fa286442d6741283855.pdf
    • https://static.usrfiles.com/ugd/70a38d_d7fc1c69cff44e938c7f6adcb0973e1f.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000448b.bin
4fc2af8d3805df2b4986a22e2e2f368df1158079060252ee45aed6d33840a602
pdf-font-stream PDF embedded font (sfnt) at offset 0x448B 5096 bytes
font_01_sfnt_off000055ce.bin
ed2f055537f936910dc3a681f1cb669316fe85b9c3a791ff28ab11fb27661f9a
pdf-font-stream PDF embedded font (sfnt) at offset 0x55CE 10976 bytes