Malicious PDF — malware analysis report

Static analysis result for SHA-256 3ef3265fb21cbb49…

MALICIOUS

PDF

43.8 KB Created: 2020-08-18 16:37:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dcee1cf5a4e4ac74f72e5d71e3438c31 SHA-1: 081e2c75570d6748d24aa041430671ffbbd97e00 SHA-256: 3ef3265fb21cbb499b6bd66a935a37c6c94045b88033abba80d0f8296e4e352f
152 Risk Score

Malware Insights

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

The PDF contains a mass of external links, many pointing to Shopify domains, but one critical link directs to a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'best sheets for bed sores' and the malicious URL, suggesting a lure to a scam or phishing page. 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.ru/pify?keyword=best+sheets+for+bed+sores
    • http://files.astarboards.com/uploads/1/3/0/7/130775653/1d36160d.pdf
    • http://xemodepa.marketplaceonmill.com/uploads/1/3/0/7/130776418/8830086.pdf
    • https://cdn.shopify.com/s/files/1/0429/1349/7247/files/affairs_cloud_july_2020.pdf
    • https://cdn.shopify.com/s/files/1/0438/5266/0901/files/wodatulumepawalomupu.pdf
    • https://cdn.shopify.com/s/files/1/0440/1692/6870/files/febokudoginere.pdf
    • https://cdn.shopify.com/s/files/1/0430/4610/9341/files/xunuxab.pdf
    • https://cdn.shopify.com/s/files/1/0431/3006/0955/files/auto_exec_bat.pdf
    • https://cdn.shopify.com/s/files/1/0435/4303/6053/files/access_database_password_recovery.pdf
    • https://cdn.shopify.com/s/files/1/0436/4481/3470/files/chess_for_windows_7_free.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/livoxigugefeguvon.pdf
    • https://cdn.shopify.com/s/files/1/0435/2707/8052/files/inductive_approach_in_teaching_grammar.pdf
    • https://cdn.shopify.com/s/files/1/0433/7297/0133/files/2673587351.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_off00006de7.bin
784135449e4afffc35b7b883e61040b6a6daed15fd2f13c0b5d02e2baefc5468
pdf-font-stream PDF embedded font (sfnt) at offset 0x6DE7 4944 bytes
font_01_sfnt_off00007eaf.bin
de3c1409d405c6aa93287d3b5584062bbcbd395cd803f7b4473ebfc039d697c3
pdf-font-stream PDF embedded font (sfnt) at offset 0x7EAF 10604 bytes