Malicious PDF — malware analysis report

Static analysis result for SHA-256 803a703edb706731…

MALICIOUS

PDF

31.5 KB Created: 2020-08-17 15:38:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 220f821ff1f6c214bfd4726f1e5b1ec4 SHA-1: 9371bd8f5ab1a05b10b4d52b1178c8d07f6e9658 SHA-256: 803a703edb70673135d5670f0ecb336cc0a36471225e8ffd6673a37cac82115b
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded links that redirect to malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK heuristic. The document body, though obfuscated, contains text suggesting it is an 'Eadms answer key biology', which is likely a lure. The presence of numerous external PDF links, many pointing to seemingly generated content, suggests a link farm used for SEO poisoning or distributing further malicious 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=eadms+answer+key+biology
    • http://nemir.texascountryweddings.com/uploads/1/3/0/7/130775732/nabum.pdf
    • http://files.huntersroots.com/uploads/1/3/1/8/131871864/lajakareseb_mixetenijo_xegosebiva_tojel.pdf
    • http://gugup.wakefieldpodiatrists.co.uk/uploads/1/3/1/3/131398101/9651453.pdf
    • http://zasiguv.amereldas.com/uploads/1/3/0/7/130739223/688989.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0430/9906/2421/files/missing_letter_worksheets_for_kindergarten.pdf
    • https://cdn.shopify.com/s/files/1/0430/7566/6073/files/zexosifuwagagiluvovejix.pdf
    • https://cdn.shopify.com/s/files/1/0432/9183/6566/files/angielski_swka_chomikuj.pdf
    • https://cdn.shopify.com/s/files/1/0429/9508/9559/files/zekoguwoxafixutizakoferij.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/86399573169.pdf
    • https://cdn.shopify.com/s/files/1/0431/6083/0116/files/gemezibesumipidupezelaw.pdf
    • https://cdn.shopify.com/s/files/1/0431/0591/0935/files/rise_of_the_guardians_book.pdf
    • https://cdn.shopify.com/s/files/1/0433/5842/1142/files/terry_eagleton_books.pdf
    • https://cdn.shopify.com/s/files/1/0437/9394/0642/files/ministry_of_finance_indonesia_annual_report.pdf
    • https://cdn.shopify.com/s/files/1/0440/2230/0822/files/enlace_quimico_metalico.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_off0000425f.bin
044780da971e6a70df01e55260ce18ea59ba960ea70c099fe0c402b6c4e5eba3
pdf-font-stream PDF embedded font (sfnt) at offset 0x425F 5500 bytes
font_01_sfnt_off00005516.bin
ff7a3cbab6615445fe1f9be43e2031319bedc8c44d52c4cb8b9e7a8f682da461
pdf-font-stream PDF embedded font (sfnt) at offset 0x5516 8396 bytes