Malicious PDF — malware analysis report

Static analysis result for SHA-256 a3b6fbce0f3d2010…

MALICIOUS

PDF

53.4 KB Created: 2020-09-04 12:40:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f63515d3718b109f86aacf79a690a91f SHA-1: bd27eb74a5b1104047c33e68d53b42f09984cdde SHA-256: a3b6fbce0f3d2010129faafbc752eb31740156297ac57554a5807bd7f2dfafee
152 Risk Score

Malware Insights

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

The PDF file contains a significant number of embedded links, many of which point to a link farm hosted on static.usrfiles.com. One critical heuristic identified a link to known malicious redirector infrastructure at 'https://ttraff.me/wix?keyword=boy+scout+uniform+patch+placement+2018'. This suggests the document's primary purpose is to lure users to malicious sites. The ML classifier also strongly indicated maliciousness.

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.me/wix?keyword=boy+scout+uniform+patch+placement+2018
    • https://static.usrfiles.com/ugd/0789d5_ce6b1ad351f446759f1bb0bb7245527f.pdf
    • https://static.usrfiles.com/ugd/3801ff_df83862a20214138b4441f64b57a7f01.pdf
    • https://static.usrfiles.com/ugd/f3cb45_f11a81a401d7483c9cf4e7234eeead1a.pdf
    • https://static.usrfiles.com/ugd/10e3af_dd18b63ea6f04f15aeb2f6a62940feea.pdf
    • https://static.usrfiles.com/ugd/b8c837_8e4350b43ae547118527007f65489b33.pdf
    • https://cdn.shopify.com/s/files/1/0435/9726/7112/files/estudio_descriptivo.pdf
    • https://cdn.shopify.com/s/files/1/0434/8097/3477/files/3942242727.pdf
    • https://cdn.shopify.com/s/files/1/0429/3486/1991/files/jajikib.pdf
    • https://cdn.shopify.com/s/files/1/0433/8876/4316/files/heat_and_mass_transfer_cengel_5th.pdf
    • https://cdn.shopify.com/s/files/1/0451/0878/9413/files/download_arabic_english_dictionary.pdf
    • https://cdn.shopify.com/s/files/1/0463/0672/1957/files/casio_g_shock_4765_manual.pdf
    • https://cdn.shopify.com/s/files/1/0434/5063/0296/files/elena_arnedo_ex_de_miguel_boyer.pdf
    • https://static.usrfiles.com/ugd/3dd68e_20096e9cca00436d910b03af31010b5c.pdf
    • https://static.usrfiles.com/ugd/b8c837_39a756f072f946c8b2b0e8b6226210bb.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_off00008f56.bin
23f0da2af6cdc349a987f00799651ca4e002bd0fe09639ebe76d87f6afaf71db
pdf-font-stream PDF embedded font (sfnt) at offset 0x8F56 5928 bytes
font_01_sfnt_off0000a366.bin
e0b5521496c3b84cea2bd28212c886f7b7640251aec78212f2700f1b83837112
pdf-font-stream PDF embedded font (sfnt) at offset 0xA366 10852 bytes