Malicious PDF — malware analysis report

Static analysis result for SHA-256 b267b478372f19d7…

MALICIOUS

PDF

40.0 KB Created: 2020-08-04 03:09:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e82230ea9047619540ea915a439aaddf SHA-1: 47a2a6fbc5bfbc3ef70365431e4c27acec21f776 SHA-256: b267b478372f19d7ba713e6b14edaac1579c3892d8c2d28089c011001e78c8d2
154 Risk Score

Malware Insights

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

The PDF contains a link to a known malicious redirector, ttraff.ru, disguised as an IELTS listening answer sheet. This redirector likely leads to further malicious content or exploits. The document body and numerous embedded URLs, many hosted on Shopify, suggest a link farm or SEO poisoning tactic to attract victims searching for specific document types. 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/pify?keyword=ielts+general+listening+answer+sheet+pdf
    • http://files.mspark.org/uploads/1/3/1/3/131379999/mubofufaw.pdf
    • http://kotasedem.bronxvillemhslibrary.com/uploads/1/3/0/7/130740249/ee9d8c6d.pdf
    • http://files.peoplemanagerssurvivalguide.com/uploads/1/3/1/4/131408572/4e6f239486.pdf
    • https://cdn.shopify.com/s/files/1/0435/1819/7912/files/9484655240.pdf
    • https://cdn.shopify.com/s/files/1/0438/5059/6512/files/sumewenofuk.pdf
    • https://cdn.shopify.com/s/files/1/0433/3774/4534/files/20861111903.pdf
    • https://cdn.shopify.com/s/files/1/0429/9885/7891/files/cool_math_games_box_man.pdf
    • https://cdn.shopify.com/s/files/1/0433/3905/5253/files/58434425087.pdf
    • https://cdn.shopify.com/s/files/1/0427/5788/2022/files/lisaxujudozigolamesefib.pdf
    • https://cdn.shopify.com/s/files/1/0435/7393/6291/files/49026071170.pdf
    • https://cdn.shopify.com/s/files/1/0434/8693/7253/files/sinibesipowirusuno.pdf
    • https://cdn.shopify.com/s/files/1/0432/6116/5723/files/12832092493.pdf
    • https://cdn.shopify.com/s/files/1/0431/2072/2080/files/buzopozasopugijedema.pdf
    • https://cdn.shopify.com/s/files/1/0431/4464/2715/files/lesojiridepulagobubu.pdf
    • https://cdn.shopify.com/s/files/1/0438/4518/9794/files/sukumo.pdf
    • https://cdn.shopify.com/s/files/1/0429/8273/6031/files/ccvc_words_worksheets.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_off00005e94.bin
94df4935d5515695f84569d4eed6659ba5a331c1fcc87e596d3fcf497c3090eb
pdf-font-stream PDF embedded font (sfnt) at offset 0x5E94 5332 bytes
font_01_sfnt_off000070c4.bin
4c65148e946f90ce4ca85f7cbc2cc5bcf04154761d75a6ebc8fdb08c26fb9d7c
pdf-font-stream PDF embedded font (sfnt) at offset 0x70C4 10000 bytes