Malicious PDF — malware analysis report

Static analysis result for SHA-256 8731f56c9576d9bc…

MALICIOUS

PDF

29.8 KB Created: 2020-08-18 14:42:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 89bee6b8b756319aaaefba014173e7e7 SHA-1: 2623260de11a3918b02646e75066208f66f6424d SHA-256: 8731f56c9576d9bcb6191d32e2b138f36c274b9adb3ff039f850c8262d583f9c
174 Risk Score

Malware Insights

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

The PDF is image-only, typical of a phishing lure, and contains a critical heuristic firing for a malicious redirector link. The embedded document body also contains the same malicious URL, suggesting the user is intended to click through to this site. The presence of multiple external PDF links, many hosted on Shopify, indicates a link farm used to obscure the malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 29 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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/pify?keyword=cute+couple+kiss+hd+wallpaper
    • http://files.natgastrucks.com/uploads/1/3/1/4/131438137/c905d5.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0427/6197/8023/files/printable_bingo_chips.pdf
    • https://cdn.shopify.com/s/files/1/0432/8266/1526/files/61137247300.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/99231100330.pdf
    • https://cdn.shopify.com/s/files/1/0433/3695/8104/files/wazezunovuvubazer.pdf
    • https://cdn.shopify.com/s/files/1/0439/8927/0686/files/top_augmented_reality_apps_android.pdf
    • https://cdn.shopify.com/s/files/1/0429/8519/3621/files/bodyboss_ultimate_body_fitness_guide.pdf
    • https://cdn.shopify.com/s/files/1/0437/4659/0872/files/88670128273.pdf
    • https://cdn.shopify.com/s/files/1/0429/5960/1830/files/74390776384.pdf
    • https://cdn.shopify.com/s/files/1/0428/0372/4455/files/lubuni.pdf
    • https://cdn.shopify.com/s/files/1/0432/9563/7659/files/80754773630.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_off00003dbe.bin
dece103558889480773d000a4a2ba76df3af09c9bea39c6b094f8110dbce249b
pdf-font-stream PDF embedded font (sfnt) at offset 0x3DBE 5220 bytes
font_01_sfnt_off00004f86.bin
e689adc45a7cea7d64be75628682654131477d49be16cff07894852e60ece3b4
pdf-font-stream PDF embedded font (sfnt) at offset 0x4F86 7968 bytes