Malicious PDF — malware analysis report

Static analysis result for SHA-256 f94db966dac84325…

MALICIOUS

PDF

44.6 KB Created: 2020-08-29 16:17:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2ec29ec65d655ffd7c9885c9e961713e SHA-1: 71ecb320f44ce45cec3703217e87f37d2bb812be SHA-256: f94db966dac84325ec5bba37d963b8dfbc8697b2fc53bc99ae21ae07fe390127
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic identifying a link to a known malicious redirector at 'ttraff.ru'. The document body, though heavily obfuscated, contains text related to 'Ielts listening practice test 111' and the malicious URL, suggesting a lure to a phishing or malware distribution site. The ML classifier also strongly flagged this PDF as malicious.

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/wix?keyword=ielts+listening+practice+test+111
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/27150836515.pdf
    • https://cdn.shopify.com/s/files/1/0434/5475/9065/files/68618390730.pdf
    • https://cdn.shopify.com/s/files/1/0431/5981/4306/files/32875709098.pdf
    • https://cdn.shopify.com/s/files/1/0435/4077/5071/files/after_interview_follow_up_email_template.pdf
    • https://cdn.shopify.com/s/files/1/0429/6248/5407/files/9515980575.pdf
    • https://cdn.shopify.com/s/files/1/0436/2086/0064/files/zuderanije.pdf
    • https://cdn.shopify.com/s/files/1/0429/3784/3871/files/2020_audi_a4_owners_manual.pdf
    • https://cdn.shopify.com/s/files/1/0430/2195/9325/files/kiwawefagoben.pdf
    • https://cdn.shopify.com/s/files/1/0437/9066/3832/files/dark_vengeance_40k.pdf
    • https://cdn.shopify.com/s/files/1/0430/0200/3619/files/32445465335.pdf
    • https://cdn.shopify.com/s/files/1/0437/6762/7928/files/fuxomatuko.pdf
    • https://static.usrfiles.com/ugd/b8c837_8a69c0444e8e4064b6760d3e758a1e9c.pdf
    • https://static.usrfiles.com/ugd/8b97dd_4021e9f20e0448b5acdb1e51aa21236a.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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005f4a.bin
50d7c5d107b4ae74250d9de2f70535e1058c14333b4908cb389da05aa6a04324
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F4A 5092 bytes
font_01_sfnt_off0000709f.bin
881eeed9618c3d90628845b4feed87f478ac334f272096c8846a0b9b3e30a7e4
pdf-font-stream PDF embedded font (sfnt) at offset 0x709F 3740 bytes
font_02_sfnt_off00007f23.bin
9e8130532efb05ba8371ad85ee92b94267b9e7323193e1dc26d77e8b9c5ab5f4
pdf-font-stream PDF embedded font (sfnt) at offset 0x7F23 10764 bytes