Malicious PDF — malware analysis report

Static analysis result for SHA-256 6d39dc0f7bfe1f73…

MALICIOUS

PDF

42.6 KB Created: 2020-08-17 11:21:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 851d233dcb0adc76cec29f8d50d55338 SHA-1: a6517a745a31a8dd7318af1f766df5a943e3fda7 SHA-256: 6d39dc0f7bfe1f735aa5943ae8ff6412038f14b1b364c7f876c653affb5f1dc1
154 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many of which point to a link farm designed to redirect users to malicious infrastructure. The primary malicious URL identified is a redirector, suggesting an attempt to obfuscate the final destination. The ML classifier strongly indicated maliciousness, and the PDF structure itself is suspicious due to the mass of external links.

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/pify?keyword=baby+happy+birthday+images+hd+free
    • http://files.cheflouiscatering.com/uploads/1/3/1/4/131407424/6742050.pdf
    • http://zugoveja.mortzheim.com/uploads/1/3/0/8/130874284/lipakeg_kanafupabejaz.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/7017/6928/files/prolactinoma_guidelines_2017.pdf
    • https://cdn.shopify.com/s/files/1/0429/5491/5993/files/12168471784.pdf
    • https://cdn.shopify.com/s/files/1/0432/4674/7805/files/lab_safety_worksheet_answers_key.pdf
    • https://cdn.shopify.com/s/files/1/0438/4745/0789/files/63384791615.pdf
    • https://cdn.shopify.com/s/files/1/0428/6044/5855/files/sebofabowetotuse.pdf
    • https://cdn.shopify.com/s/files/1/0430/0092/2261/files/96229534924.pdf
    • https://cdn.shopify.com/s/files/1/0436/4324/0606/files/anglo_american_literature_answer_key.pdf
    • https://cdn.shopify.com/s/files/1/0432/2151/6449/files/71637566728.pdf
    • https://cdn.shopify.com/s/files/1/0443/9402/1030/files/55127077480.pdf
    • https://cdn.shopify.com/s/files/1/0429/9476/1877/files/27282915620.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_off0000679c.bin
fa55595b4e8eeb76039300d866ac39895fd744adf7f7607803023bdd98527269
pdf-font-stream PDF embedded font (sfnt) at offset 0x679C 5712 bytes
font_01_sfnt_off00007aea.bin
6104c1606ef1c1098e922bcbad254d938146f363ad9054f4de804e91dad18756
pdf-font-stream PDF embedded font (sfnt) at offset 0x7AEA 10088 bytes