Malicious PDF — malware analysis report

Static analysis result for SHA-256 8bad396b77cfcd13…

MALICIOUS

PDF

42.0 KB Created: 2020-08-12 21:23:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 0e4b2ba1cccd47ec1569fdba1590e73b SHA-1: 9528c55cc255783cfb2a9a8a4d98e2eb37f0a571 SHA-256: 8bad396b77cfcd13343089096ec110b4536ebedf491a16dfa1846fc88c902830
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many of which point to a link farm hosted on Shopify. One prominent link redirects through 'ttraff.ru', a known malicious redirector, with a query suggesting a lure for 'best parenting books pdf'. The ML classifier strongly indicated maliciousness, and the PDF structure itself is indicative of a link-farming SEO spam campaign.

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/wb?keyword=best%20parenting%20books%20pdf
    • http://files.norcalsmartvestorpro.com/uploads/1/3/2/7/132710655/96f0fa3.pdf
    • http://files.janetruth.com/uploads/1/3/0/8/130873807/5290ef67497c.pdf
    • http://vimepufim.thedailyencounter.org/uploads/1/3/1/3/131380429/6644376.pdf
    • https://cdn.shopify.com/s/files/1/0432/6726/0582/files/ginarodoge.pdf
    • https://cdn.shopify.com/s/files/1/0437/5255/4657/files/zofenuriwabitomuloras.pdf
    • https://cdn.shopify.com/s/files/1/0446/6225/9865/files/nedoruxariboturikomoxo.pdf
    • https://cdn.shopify.com/s/files/1/0437/5448/7957/files/63798425086.pdf
    • https://cdn.shopify.com/s/files/1/0431/4392/1820/files/likasobajekefe.pdf
    • https://cdn.shopify.com/s/files/1/0430/7219/2669/files/69391456435.pdf
    • https://cdn.shopify.com/s/files/1/0429/2152/5407/files/brosur_kusen_aluminium_alexindo.pdf
    • https://cdn.shopify.com/s/files/1/0435/9825/0146/files/haldol_decanoate_package_insert.pdf
    • https://cdn.shopify.com/s/files/1/0431/7764/0092/files/19210278674.pdf
    • https://cdn.shopify.com/s/files/1/0431/9323/7665/files/11402211078.pdf
    • https://cdn.shopify.com/s/files/1/0432/9675/1771/files/precalculus_with_limits_chapter_7.pdf
    • https://cdn.shopify.com/s/files/1/0432/5005/7373/files/al_azkar_imam_nawawi_download.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_off00006646.bin
1a63cbbc1b749b66b770d8c6ceaefcbe480f6a954e3b3ab03e545a6077d30e88
pdf-font-stream PDF embedded font (sfnt) at offset 0x6646 5428 bytes
font_01_sfnt_off000078c9.bin
c681c0ebe9503c502b3c66a9060ba3561ec1ed53c130845065e14156db0f95b0
pdf-font-stream PDF embedded font (sfnt) at offset 0x78C9 10120 bytes