Malicious PDF — malware analysis report

Static analysis result for SHA-256 50cdc9eab0990f26…

MALICIOUS

PDF

39.4 KB Created: 2020-08-23 00:12:24 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 35be166584771f594eaf29acaf67d06d SHA-1: aacd1435ae1d19c76cd889b932539241ed8ad22e SHA-256: 50cdc9eab0990f2656998a9706e21ffe2ea011e80d89596dca6af84a3cfbc79f
152 Risk Score

Malware Insights

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

The PDF contains a heuristic firing for a malicious redirector link, directing users to 'https://ttraff.ru/pify?keyword=worksheets+for+kindergarten+pattern+writing'. Additionally, it exhibits characteristics of a PDF link farm, embedding numerous external links, with a significant portion pointing to Shopify domains. The ML classifier also strongly indicated maliciousness. The document body, though partially corrupted, contains the same malicious URL, suggesting a lure to external content.

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=worksheets+for+kindergarten+pattern+writing
    • http://lutetefe.bexbourne.co.uk/uploads/1/3/2/7/132712237/f1bde4233dda491.pdf
    • https://cdn.shopify.com/s/files/1/0431/0161/8327/files/mogenutixat.pdf
    • https://cdn.shopify.com/s/files/1/0437/9607/0560/files/25998466101.pdf
    • https://cdn.shopify.com/s/files/1/0434/4178/2950/files/6184792333.pdf
    • https://cdn.shopify.com/s/files/1/0435/2393/2311/files/padajosepuwo.pdf
    • https://cdn.shopify.com/s/files/1/0444/3848/7206/files/sony_bdps_350.pdf
    • https://cdn.shopify.com/s/files/1/0434/0708/1622/files/string_to_int_c.pdf
    • https://cdn.shopify.com/s/files/1/0434/6534/3133/files/fibujeru.pdf
    • https://cdn.shopify.com/s/files/1/0438/6727/5424/files/77266699720.pdf
    • https://cdn.shopify.com/s/files/1/0437/2358/7736/files/tenabepafofir.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/ferenap.pdf
    • https://cdn.shopify.com/s/files/1/0431/2884/8538/files/xutulatozekar.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_off00005b08.bin
0492955cbf1342f5eba02dcae03b68ca7106379cd873b882aeaa1e0fac7b7471
pdf-font-stream PDF embedded font (sfnt) at offset 0x5B08 5440 bytes
font_01_sfnt_off00006da4.bin
7b23555e27dac770e060e9d46060d319e16da1e93bb17436bd7555deba46816f
pdf-font-stream PDF embedded font (sfnt) at offset 0x6DA4 10400 bytes