Malicious PDF — malware analysis report

Static analysis result for SHA-256 b9bc7a9b7248d3d8…

MALICIOUS

PDF

39.5 KB Created: 2020-08-18 22:39:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: dfe462b4a2cb778385ce05874637b7ef SHA-1: c8c2e3b5685281fb1224cb86d0d29150e9eb1f52 SHA-256: b9bc7a9b7248d3d80469d6f58ccca588c313efee4a7710bb798a07f14ba535ff
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a mass external link farm, with the primary link directing to a malicious redirector. The document body, though heavily obfuscated, contains text related to 'Wavepad free audio editor app for android', suggesting a lure for users seeking software. The ML classifier strongly indicated maliciousness, and the presence of numerous links to external PDFs, many hosted on Shopify, points to a content-driven phishing or malware distribution attempt.

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=wavepad+free+audio+editor+app+for+android
    • http://files.sherriobermark.com/uploads/1/3/0/7/130775916/dogafetagel-xubujal.pdf
    • http://files.maggieessig.com/uploads/1/3/1/4/131438437/rumifiv.pdf
    • http://rudegekef.inspiredfictionbooks.com/uploads/1/3/1/3/131380606/84b856016c2b.pdf
    • http://mabuno.lebonearchitects.com/uploads/1/3/0/8/130814328/jovikukupovebebem.pdf
    • https://cdn.shopify.com/s/files/1/0431/3550/0439/files/5340204349.pdf
    • https://cdn.shopify.com/s/files/1/0428/4389/8019/files/pajutibolerezodo.pdf
    • https://cdn.shopify.com/s/files/1/0428/2934/9030/files/writing_conclusion_sentences_worksheets.pdf
    • https://cdn.shopify.com/s/files/1/0431/4356/1376/files/dejogimeparubasired.pdf
    • https://cdn.shopify.com/s/files/1/0439/5981/2254/files/82328233401.pdf
    • https://cdn.shopify.com/s/files/1/0434/5407/0951/files/51461250666.pdf
    • https://cdn.shopify.com/s/files/1/0432/9432/6939/files/71617590415.pdf
    • https://cdn.shopify.com/s/files/1/0432/4071/8496/files/55712689796.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_off00005d0c.bin
fa8213a717b6aba450f3c82e11134173ff7a33f99a09312646aa7343735bb940
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D0C 4900 bytes
font_01_sfnt_off00006dd8.bin
8c4958861dd4640bfc8cf0925027aa9395dcb4c7afcc7e7a9cd4436d18b9d8f7
pdf-font-stream PDF embedded font (sfnt) at offset 0x6DD8 10660 bytes