Malicious PDF — malware analysis report

Static analysis result for SHA-256 21761ac5521123f1…

MALICIOUS

PDF

46.6 KB Created: 2020-07-29 12:24:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fa9af841e67e3ea0a984ecfc7d3649b4 SHA-1: b00bf120f45aa442fe3b574373cde18efd127414 SHA-256: 21761ac5521123f1a47fd8c43d9d4868bf64dafd78d5bb97b8750b603cfa1a6c
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one specifically identified as a malicious redirector. The document body, though heavily obfuscated, suggests a lure related to art, likely to entice users to click the malicious links. The ML classifier also strongly indicated maliciousness.

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=abject+art+repulsion+and+desire+in+american+art+pdf
    • http://files.bornadventuregear.com/uploads/1/3/2/6/132682076/3056093.pdf
    • http://files.dkgalphaalpha.org/uploads/1/3/2/6/132696558/8595452.pdf
    • http://files.pattersonfan.com/uploads/1/3/1/4/131482931/tupowuva.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/58085676994.pdf
    • https://cdn.shopify.com/s/files/1/0430/0763/9711/files/55803537426.pdf
    • https://cdn.shopify.com/s/files/1/0433/5537/3720/files/53603195507.pdf
    • https://cdn.shopify.com/s/files/1/0430/9381/9541/files/musuvagaxa.pdf
    • https://cdn.shopify.com/s/files/1/0434/6393/4109/files/26850443230.pdf
    • https://cdn.shopify.com/s/files/1/0430/5358/0437/files/29712345567.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/nejoxalivivurotuzepebibus.pdf
    • https://cdn.shopify.com/s/files/1/0431/5820/8674/files/kutaluwegesizokuvowure.pdf
    • https://cdn.shopify.com/s/files/1/0431/2065/6545/files/pemuti.pdf
    • https://cdn.shopify.com/s/files/1/0430/0275/7281/files/rulubuxikeg.pdf
    • https://cdn.shopify.com/s/files/1/0428/2597/3916/files/mewaxolazamewesituzumixo.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/
    • https://cdn.shopify.com/s/files/1/0434/6393/4109/files/2685

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007909.bin
09d686edd9b7b4e1b28610cf84268071df7f216a61dc68f8dc6072c22c75def8
pdf-font-stream PDF embedded font (sfnt) at offset 0x7909 5388 bytes
font_01_sfnt_off00008b36.bin
8cc77c308b8f802a27f49ec4aca883c2d68399ab3bc35020250f86c218faecc2
pdf-font-stream PDF embedded font (sfnt) at offset 0x8B36 9980 bytes