Malicious PDF — malware analysis report

Static analysis result for SHA-256 31493919f31a5781…

MALICIOUS

PDF

43.0 KB Created: 2020-08-10 23:18:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 204aff69e7c8150614d06316c5ee9dde SHA-1: f7597a22ed19c55eba6cf5d6e24a9b0f91dc46ad SHA-256: 31493919f31a5781b8004d3b3613a7789610726a08a7036ab64fb30a4315032e
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF contains a lure for a "caregiver burnout quiz" and embeds a significant number of links to external PDF files, including a known malicious redirector. The ML classifier strongly indicates maliciousness. The primary attack pattern involves redirecting users to malicious infrastructure via embedded links, likely for further exploitation or credential harvesting.

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=caregiver+burnout+quiz+pdf
    • http://files.arlingtonmsband.com/uploads/1/3/1/6/131606087/ddee7.pdf
    • http://files.blacksheep-kitchen.net/uploads/1/3/1/3/131381078/riwosog_vugolex_wesugumi.pdf
    • http://files.brownwoodlake.com/uploads/1/3/1/3/131380292/wusogiz_kadokid_jimusab.pdf
    • http://bigavuvaj.westequip.com/uploads/1/3/1/4/131437792/tojabavulexo.pdf
    • http://netojuv.wehikedit.com/uploads/1/3/0/8/130814328/6495439.pdf
    • https://cdn.shopify.com/s/files/1/0428/3164/2780/files/rijimug.pdf
    • https://cdn.shopify.com/s/files/1/0435/8651/9208/files/86832887935.pdf
    • https://cdn.shopify.com/s/files/1/0432/6447/5299/files/truck_dispatcher_training.pdf
    • https://cdn.shopify.com/s/files/1/0430/6888/3097/files/kuzowugekuvosi.pdf
    • https://cdn.shopify.com/s/files/1/0437/3485/9941/files/50168762460.pdf
    • https://cdn.shopify.com/s/files/1/0438/4459/9958/files/model_assisted_survey_sampling.pdf
    • https://cdn.shopify.com/s/files/1/0432/8315/3056/files/third_angle_orthographic_projection.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/tevegijetowid.pdf
    • https://cdn.shopify.com/s/files/1/0432/3203/4976/files/asat_test_papers.pdf
    • https://cdn.shopify.com/s/files/1/0431/0836/8545/files/sabriel_old_kingdom_book_1.pdf
    • https://cdn.shopify.com/s/files/1/0433/7506/7297/files/20544477074.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_off000069cb.bin
c9137840429261fe270b2707caffdd22ddd4b00001defc5b80bc5b4990ff36c7
pdf-font-stream PDF embedded font (sfnt) at offset 0x69CB 5280 bytes
font_01_sfnt_off00007bd2.bin
4a903937b4fb11474da3fcb6753bf9cda4e7cb93b9aa3de80719ad0dae21b134
pdf-font-stream PDF embedded font (sfnt) at offset 0x7BD2 10292 bytes