Malicious PDF — malware analysis report

Static analysis result for SHA-256 c71cbec973b52197…

MALICIOUS

PDF

49.9 KB Created: 2020-07-28 20:03:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: fd5ab8598376140111abb75ce1061068 SHA-1: 8fd081b4886d1db9e435e980baed0a370bd97b0a SHA-256: c71cbec973b52197b53cf45c6d01b1f712361f386c390275a0f898915425bfe4
152 Risk Score

Malware Insights

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

The PDF was flagged by multiple critical heuristics for containing malicious redirector links and a link farm. The ML classifier also strongly indicated maliciousness. The document body, though heavily obfuscated, appears to contain metadata related to PDF generation and potentially search engine optimization keywords. The primary malicious indicator is the presence of numerous links, with https://ttraff.ru/pify?keyword=science+five+kingdoms+worksheets being a notable example pointing to known malicious infrastructure.

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=science+five+kingdoms+worksheets
    • http://files.nunes-ueno.com/uploads/1/3/1/6/131606631/jugifibo.pdf
    • http://files.srgchi.org/uploads/1/3/1/3/131379951/zitejumewibopux_bajugetelor_dobiwezo_golubimuruz.pdf
    • http://files.thecharlie2323.com/uploads/1/3/0/7/130739369/2800536.pdf
    • http://files.srgchi.org
    • https://cdn.shopify.com/s/files/1/0429/6074/8695/files/nokopamugepakavegi.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/95509007145.pdf
    • https://cdn.shopify.com/s/files/1/0431/9808/7328/files/58777212528.pdf
    • https://cdn.shopify.com/s/files/1/0431/3595/9191/files/fitapemanat.pdf
    • https://cdn.shopify.com/s/files/1/0429/0209/3987/files/59657547861.pdf
    • https://cdn.shopify.com/s/files/1/0432/4343/8242/files/26177438927.pdf
    • https://cdn.shopify.com/s/files/1/0440/1112/6942/files/12641483403.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/jivanup.pdf
    • https://cdn.shopify.com/s/files/1/0440/5598/6341/files/3307361380.pdf
    • https://cdn.shopify.com/s/files/1/0433/0507/4838/files/11527059019.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_off0000861d.bin
f4296691b646812dcd565781b0660e2d7dccdacee982f20a35733fecd16e2cc5
pdf-font-stream PDF embedded font (sfnt) at offset 0x861D 5300 bytes
font_01_sfnt_off00009804.bin
cf9fc791ed46a244a626e3c5fd1aa95f6d9775e19e04b6a255c683fb23431a74
pdf-font-stream PDF embedded font (sfnt) at offset 0x9804 10252 bytes