Malicious PDF — malware analysis report

Static analysis result for SHA-256 4e8db10b8c3bd385…

MALICIOUS

PDF

42.3 KB Created: 2020-08-11 17:07:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0fa11c3dd25858fb193924feae40f812 SHA-1: 3b3250ace0fa0a0432f619f6124a327abcd28311 SHA-256: 4e8db10b8c3bd3854171f5949df1ae32777426bdf3bada521290359e966b6b42
152 Risk Score

Malware Insights

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

The PDF was flagged by multiple critical heuristics for containing malicious redirector links and a link farm. The ML classifier also strongly indicated maliciousness. The document body contains text and embedded URLs, including a primary malicious redirector URL. The presence of numerous links to external PDFs, many hosted on Shopify, suggests an attempt to obscure the final malicious destination.

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.com/pify?keyword=the+enormous+crocodile+story+book+pdf
    • http://files.bostonareamaskinitiative.com/uploads/1/3/1/4/131437941/36468593beb3f56.pdf
    • http://files.okstatecrew.org/uploads/1/3/2/6/132683000/8795943.pdf
    • http://files.downrivermortgageone.com/uploads/1/3/2/6/132695829/dixuvawumorukef_mutibimodo_mujezodomuxu_sarakadese.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/kesazemoluvumexon.pdf
    • https://cdn.shopify.com/s/files/1/0434/3011/7542/files/albert_camus_libros_gratis.pdf
    • https://cdn.shopify.com/s/files/1/0437/2201/4870/files/limitations_of_beer_lambert_law.pdf
    • https://cdn.shopify.com/s/files/1/0434/2094/2486/files/79333835584.pdf
    • https://cdn.shopify.com/s/files/1/0431/8858/4605/files/fibidakojepasebope.pdf
    • https://cdn.shopify.com/s/files/1/0434/8860/8418/files/wukikipimorijewededuwi.pdf
    • https://cdn.shopify.com/s/files/1/0432/8115/4214/files/25447989025.pdf
    • https://cdn.shopify.com/s/files/1/0430/6976/7842/files/class_10_science_chapter_11_notes.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/47184882359.pdf
    • https://cdn.shopify.com/s/files/1/0429/4829/6863/files/dd_form_1149.pdf
    • https://cdn.shopify.com/s/files/1/0427/4028/5607/files/87205408217.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_off0000669c.bin
7d089855fbe07c0301fb2cb2408a871d58d46a70722faaf73750efca74244afd
pdf-font-stream PDF embedded font (sfnt) at offset 0x669C 5440 bytes
font_01_sfnt_off000078f3.bin
a3394861b61a619207f8022c54f3a341555a4d3de486a0e4872f0b6872d1a1c0
pdf-font-stream PDF embedded font (sfnt) at offset 0x78F3 10312 bytes