Malicious PDF — malware analysis report

Static analysis result for SHA-256 766e8d51a833fbb2…

MALICIOUS

PDF

57.9 KB Created: 2020-08-10 15:13:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 727e4a2c8339ba8be27744e32f452520 SHA-1: 85545a791e4a10a60240f4ad4fac99e3718e4682 SHA-256: 766e8d51a833fbb2f85af66f00a7f347c15f23d7686b6b9ee4813bd100622ef3
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded links, many of which point to a link farm designed for SEO manipulation. One prominent URL, 'https://ttraff.ru/pify?keyword=algebraic+functions+worksheet+pdf', is flagged as malicious redirector infrastructure. The document body, though heavily obfuscated, also contains this URL, suggesting an attempt to drive traffic to malicious sites under the guise of educational content.

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=algebraic+functions+worksheet+pdf
    • http://files.spartanadvantage.com/uploads/1/3/1/4/131453221/xawigoloworaleno.pdf
    • http://files.madebypaulineny.com/uploads/1/3/1/4/131455024/betefuso.pdf
    • http://files.timothymax.org/uploads/1/3/1/3/131384127/fejip.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0438/1219/2413/files/kefipidawemomafibatamib.pdf
    • https://cdn.shopify.com/s/files/1/0433/3902/2494/files/estados_financieros_ejemplos.pdf
    • https://cdn.shopify.com/s/files/1/0431/8907/6117/files/49248847593.pdf
    • https://cdn.shopify.com/s/files/1/0430/6888/3098/files/amar_ujala_news_paper_file.pdf
    • https://cdn.shopify.com/s/files/1/0431/6971/0242/files/85813731562.pdf
    • https://cdn.shopify.com/s/files/1/0433/6487/6453/files/84605717586.pdf
    • https://cdn.shopify.com/s/files/1/0432/8528/2980/files/24081327505.pdf
    • https://cdn.shopify.com/s/files/1/0434/3136/2725/files/dazoda.pdf
    • https://cdn.shopify.com/s/files/1/0434/9375/2997/files/associative_memory_in_computer_architecture.pdf
    • https://cdn.shopify.com/s/files/1/0433/3699/0885/files/vemulodusobifafuwuribaj.pdf
    • https://cdn.shopify.com/s/files/1/0436/1427/3693/files/myrkursablt_nightside_of_the_old_norse_mythology.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000995d.bin
6991b94727d1045e207000321725e6805f9de6930803d6f468f648965b3cd894
pdf-font-stream PDF embedded font (sfnt) at offset 0x995D 5700 bytes
font_01_sfnt_off0000accf.bin
6e57d13f436bfe5fd152c741d3afe6e99643b06c210757691c257203474ad588
pdf-font-stream PDF embedded font (sfnt) at offset 0xACCF 14268 bytes