Malicious PDF — malware analysis report

Static analysis result for SHA-256 db9984c5725f708e…

MALICIOUS

PDF

39.6 KB Created: 2020-08-15 12:31:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: ca1ce0a0516dd559a3a098e4bd222a90 SHA-1: fd1bd70b08216246dace8561e830572c6eec50b0 SHA-256: db9984c5725f708e9926ad48a5e9db2fab4075bf12ed7a4b2b90fffbb6360e48
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one specifically pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text related to a worksheet and the malicious URL, suggesting a lure to a phishing or malware distribution site. The ML classifier strongly flagged this PDF as malicious.

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.cc/wb?keyword=6th%20grade%20order%20of%20operations%20with%20exponents%20worksheet
    • http://files.americastrumpet.com/uploads/1/3/0/9/130969446/puvederin.pdf
    • http://files.rivalsinc.com/uploads/1/3/0/9/130970009/betovunozaniloxomesu.pdf
    • http://lobada.alpacasofaledo.com/uploads/1/3/0/7/130739835/fawepunozipisixas.pdf
    • http://files.oliviadummer.com/uploads/1/3/2/6/132695596/mobikojew.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/67641838088.pdf
    • https://cdn.shopify.com/s/files/1/0435/4765/6351/files/vajonipiv.pdf
    • https://cdn.shopify.com/s/files/1/0447/9628/0993/files/alvino_augusto_de_s.pdf
    • http://files.armen.people.ua.edu/uploads/1/3/0/8/130814052/f08af2562.pdf
    • https://cdn.shopify.com/s/files/1/0431/0145/4496/files/tratat_de_chimie_anorganica.pdf
    • https://cdn.shopify.com/s/files/1/0441/2047/3752/files/xobubulusakofu.pdf
    • https://cdn.shopify.com/s/files/1/0431/5915/8940/files/midijudidi.pdf
    • https://cdn.shopify.com/s/files/1/0437/6199/1841/files/etc_hosts_windows_7.pdf
    • https://cdn.shopify.com/s/files/1/0447/8015/9142/files/el_barbero_de_sevilla_rossini.pdf
    • https://cdn.shopify.com/s/files/1/0437/1136/5288/files/92585388044.pdf
    • https://cdn.shopify.com/s/files/1/0435/2750/4024/files/medical_certificate_format_for_sick_leave_for_employees.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_off00005bd6.bin
39d204d40a7cb920ffdef13b49eee18424454db620320c53bc9d3b8c8722141f
pdf-font-stream PDF embedded font (sfnt) at offset 0x5BD6 5552 bytes
font_01_sfnt_off00006ed1.bin
c78e82baaded64026182a9ee18a4377eaef23482084b76d71b8d215f869d4f0b
pdf-font-stream PDF embedded font (sfnt) at offset 0x6ED1 10060 bytes