Malicious PDF — malware analysis report

Static analysis result for SHA-256 f775c1db461c1a1d…

MALICIOUS

PDF

41.9 KB Created: 2020-08-15 03:24:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f99f8fe0b8b69fc2cd07141a6dbba6bd SHA-1: 5a7145b3c4a05954169712488f5ceebe407964e8 SHA-256: f775c1db461c1a1dfff2cbaec4600094679e79209310f58d4a728e4561f4ebc3
152 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.ru, which is disguised as a search result for free PDF editor software. The document also features a large number of embedded links to various PDF files hosted on Shopify, likely an attempt to manipulate search engine results for the malicious link. The ML classifier 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.ru/wb?keyword=foxit%20pdf%20editor%20gratis%20full
    • http://files.efmracing.com/uploads/1/3/1/3/131383943/tirakavonu-gopefomonidimij-fotedamojulo-posugazizajap.pdf
    • http://bigukazos.napashuttle.net/uploads/1/3/0/8/130873995/muzata-zosigesu.pdf
    • https://cdn.shopify.com/s/files/1/0431/4074/3329/files/english_phonetic_spelling_alphabet.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/39748763391.pdf
    • https://cdn.shopify.com/s/files/1/0431/4995/1138/files/femodago.pdf
    • https://cdn.shopify.com/s/files/1/0431/9520/3745/files/65618155087.pdf
    • https://cdn.shopify.com/s/files/1/0431/0849/9618/files/bexejomumazitukenusam.pdf
    • https://cdn.shopify.com/s/files/1/0433/6245/1611/files/senopo.pdf
    • https://cdn.shopify.com/s/files/1/0430/8199/0295/files/fegotubekowad.pdf
    • https://cdn.shopify.com/s/files/1/0432/5759/4011/files/11141874676.pdf
    • https://cdn.shopify.com/s/files/1/0433/5301/4423/files/58270455648.pdf
    • https://cdn.shopify.com/s/files/1/0439/5817/3854/files/65002082438.pdf
    • https://cdn.shopify.com/s/files/1/0434/5089/2454/files/nadigepiju.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/52209678420.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_off0000655a.bin
7d7f2d02b08650b50b2eb8f0b238422be4ffca9c7a7511a323601fe0c2d4978c
pdf-font-stream PDF embedded font (sfnt) at offset 0x655A 5232 bytes
font_01_sfnt_off00007740.bin
fe04dd5d48372a5c5b838f013def4cef6d3550abd95ace5628778a857d367af3
pdf-font-stream PDF embedded font (sfnt) at offset 0x7740 10540 bytes