Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8b8f0b536f75f63…

MALICIOUS

PDF

39.9 KB Created: 2020-08-19 14:32:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cd635e527fb3e6935fe896ff7f20c15e SHA-1: 8ba4cadd1cd3760c60a8ec453134427b2be9cffd SHA-256: a8b8f0b536f75f630ad3fef8dd0cfa62455d2d3e9494de00e3fe6ebc33e76cfc
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, a technique often used to create link farms for SEO manipulation or to redirect users to malicious sites. One of the embedded URLs, 'https://ttraff.cc/pify?keyword=game+wallpaper+hd++for+android+mobile', is flagged as a known malicious redirector. The ML classifier also strongly indicated maliciousness. The document body contains garbled text along with the suspicious URL, suggesting an attempt to obscure the malicious intent.

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=game+wallpaper+hd++for+android+mobile
    • http://files.kenmoreta.org/uploads/1/3/1/3/131380730/gufekafof_dusabadujunole_kujixababijobog.pdf
    • http://files.teaching.yfolajimi.com/uploads/1/3/1/8/131856907/vubefoz.pdf
    • http://files.runamokfarm.com/uploads/1/3/1/4/131437680/nawizofij.pdf
    • http://zorali.wdspa.com/uploads/1/3/1/8/131871479/326feec4.pdf
    • https://cdn.shopify.com/s/files/1/0434/0924/4317/files/vitoxokalatorosuvinojirus.pdf
    • https://cdn.shopify.com/s/files/1/0433/8201/4108/files/geometry_word_problems_worksheets_with_answers.pdf
    • https://cdn.shopify.com/s/files/1/0433/6310/6968/files/mowororibaxusugikani.pdf
    • https://cdn.shopify.com/s/files/1/0434/3493/4429/files/35014001886.pdf
    • https://cdn.shopify.com/s/files/1/0429/0222/5059/files/pufebame.pdf
    • https://cdn.shopify.com/s/files/1/0429/0763/1782/files/buvibugadomeraverizotujow.pdf
    • https://cdn.shopify.com/s/files/1/0432/2128/7080/files/xexabit.pdf
    • https://cdn.shopify.com/s/files/1/0429/2853/7753/files/fussball_manager_2019_ea.pdf
    • https://cdn.shopify.com/s/files/1/0437/3767/7989/files/22688810620.pdf
    • https://cdn.shopify.com/s/files/1/0427/6014/3014/files/61732313414.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_off00005d80.bin
61a5675135cb7feb04857077568efa69d9a2fd84e65c2d678f2c0841fe1db0a7
pdf-font-stream PDF embedded font (sfnt) at offset 0x5D80 5368 bytes
font_01_sfnt_off00006fad.bin
2ef8863758342872e8403e78b26ca732eb005c8cf753c9168218f051aed7e056
pdf-font-stream PDF embedded font (sfnt) at offset 0x6FAD 10332 bytes