Malicious PDF — malware analysis report

Static analysis result for SHA-256 b76b0e03554a5609…

MALICIOUS

PDF

40.7 KB Created: 2020-08-15 01:12:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: db82b6e7bb839659c9a18833d6add793 SHA-1: 9272f302c59976acac517516680d6dc0f3f5a519 SHA-256: b76b0e03554a560910266edeed6c8005a98cd8947b5f5a9190f25e6a1e9884cf
152 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, many pointing to PDF files hosted on various domains. One of these links, https://ttraff.ru/pify?keyword=darkening+of+tristram+2019+guide, is identified as a malicious redirector. The ML classifier also strongly indicated maliciousness. The document body itself is largely unreadable binary data, but the presence of the link farm and the malicious redirector suggest a delivery mechanism for further malicious 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=darkening+of+tristram+2019+guide
    • http://files.futfemuniversal.com/uploads/1/3/2/8/132814272/faduxubikitorazurof.pdf
    • http://files.jorpasimart.com/uploads/1/3/1/8/131856326/90d0772b3.pdf
    • http://files.sarahdionna.com/uploads/1/3/0/7/130776655/xafunelesarutid.pdf
    • https://cdn.shopify.com/s/files/1/0438/4853/2128/files/xesajelupowureze.pdf
    • https://cdn.shopify.com/s/files/1/0431/2891/4074/files/rewapetozokomulez.pdf
    • https://cdn.shopify.com/s/files/1/0436/7033/9737/files/72955822548.pdf
    • https://cdn.shopify.com/s/files/1/0433/4272/5275/files/34038306428.pdf
    • https://cdn.shopify.com/s/files/1/0438/3725/9936/files/32787513029.pdf
    • https://cdn.shopify.com/s/files/1/0433/8024/4643/files/17295194011.pdf
    • https://cdn.shopify.com/s/files/1/0433/5812/6245/files/84722806325.pdf
    • https://cdn.shopify.com/s/files/1/0433/6667/8696/files/uk_address_in_us_format.pdf
    • https://cdn.shopify.com/s/files/1/0429/6169/8969/files/running_total_java.pdf
    • https://cdn.shopify.com/s/files/1/0431/6191/1458/files/5483613414.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_off0000608a.bin
b75dbe009b95b800cebc2d7e8f0e90a29531d827741038cd9c557b750ff819a0
pdf-font-stream PDF embedded font (sfnt) at offset 0x608A 5740 bytes
font_01_sfnt_off0000740c.bin
c8aecdb237bca2bc44edcf0e8d2569b205da766ba3281c8742f07ca49b032e14
pdf-font-stream PDF embedded font (sfnt) at offset 0x740C 9952 bytes