Malicious PDF — malware analysis report

Static analysis result for SHA-256 99ce8dfd4f596311…

MALICIOUS

PDF

45.7 KB Created: 2020-08-30 14:19:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c4d3b00e1a18e5ee6944aa1c24da2c71 SHA-1: 3dddb2e76037e08b2782d066df8b880032f27921 SHA-256: 99ce8dfd4f5963118821fac09475e2b4a3a5535c69ddcf20865c9662aa4019ea
152 Risk Score

Malware Insights

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

The PDF file was flagged as malicious by a machine learning classifier and contains a critical heuristic indicating a link to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains the URL 'https://ttraff.ru/wix?keyword=checksum+algorithm+pdf', which is also listed as a malicious redirector. The presence of numerous other links, many pointing to Shopify and static.usrfiles.com, suggests a link farm or SEO poisoning attempt to distribute 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.ru/wix?keyword=checksum+algorithm+pdf
    • https://cdn.shopify.com/s/files/1/0429/1110/5191/files/xenorinawowipa.pdf
    • https://cdn.shopify.com/s/files/1/0438/3830/8512/files/57649286846.pdf
    • https://cdn.shopify.com/s/files/1/0429/6641/7571/files/xilebote.pdf
    • https://cdn.shopify.com/s/files/1/0429/6582/7747/files/wobedubosafexunisog.pdf
    • https://static.usrfiles.com/ugd/b8c837_6ac85aa85a6c4456be04a1ff789b1937.pdf
    • https://static.usrfiles.com/ugd/2e4eb4_05a3632d07a4429cbd4675bf6c4487c8.pdf
    • https://static.usrfiles.com/ugd/8a419d_52a01211bbb846a7bd30163370f496e0.pdf
    • https://static.usrfiles.com/ugd/b8c837_8074e4e6fb15479d8a3e200b9c09d4bb.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/27621352833.pdf
    • https://cdn.shopify.com/s/files/1/0461/7194/7161/files/62152147508.pdf
    • https://static.usrfiles.com/ugd/362633_1ea66eaab0bb4f78a4c1ea445e9aca76.pdf
    • https://static.usrfiles.com/ugd/02beb7_73487f9223e54bb48d55159bef4ad61f.pdf
    • https://static.usrfiles.com/ugd/40b9e6_5b8cbb6bd2c24178a3e89b7ec29b6f39.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000066cd.bin
9bc697196efb81577a4b30afb247fa3e69420efebde4f381647b74d4406e8915
pdf-font-stream PDF embedded font (sfnt) at offset 0x66CD 5432 bytes
font_01_sfnt_off0000794e.bin
69280ed3bc467489b97a9721f62281317ed50bb8e96cc88e4c1bbc6ddef08d41
pdf-font-stream PDF embedded font (sfnt) at offset 0x794E 10144 bytes
font_02_sfnt_off00009c04.bin
4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3
pdf-font-stream PDF embedded font (sfnt) at offset 0x9C04 4324 bytes