Malicious PDF — malware analysis report

Static analysis result for SHA-256 3cd7a7d443672c41…

MALICIOUS

PDF

34.5 KB Created: 2020-08-09 07:45:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f8a91ec6a9d6c36f584bc4c46d141a12 SHA-1: 5d591ae64eede8952e5e831b4652d7e66e1cfa57 SHA-256: 3cd7a7d443672c41b55f52f027f9267d0763ac3ce7d2dc74a5980ff616a1c7b9
152 Risk Score

Malware Insights

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

The PDF file contains a large number of embedded links, masquerading as a free dictionary, which is a common lure for SEO poisoning attacks. The primary link directs to a known malicious redirector, ttraff.ru, which likely serves as a gateway to further malicious content. The ML classifier strongly indicated maliciousness, and the PDF structure itself is indicative of a link farm designed to manipulate search engine results.

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=diccionario+hebreo+biblico+pdf+gratis
    • http://files.jimcrydermanrmt.com/uploads/1/3/1/4/131438282/dediwesikexajexoz.pdf
    • http://files.madforlife.org/uploads/1/3/1/8/131871852/kefomazegoba.pdf
    • http://files.rbt247.com/uploads/1/3/1/8/131858044/c72dc.pdf
    • http://files.chirnsidedevelopment.org.uk/uploads/1/3/1/0/131070488/6574189.pdf
    • https://cdn.shopify.com/s/files/1/0433/8260/3927/files/29780078567.pdf
    • https://cdn.shopify.com/s/files/1/0436/5670/8254/files/21302375475.pdf
    • https://cdn.shopify.com/s/files/1/0431/4379/0760/files/18179979663.pdf
    • https://cdn.shopify.com/s/files/1/0429/6366/5055/files/gaguwopel.pdf
    • https://cdn.shopify.com/s/files/1/0448/0391/5933/files/biodata_sample_download.pdf
    • https://cdn.shopify.com/s/files/1/0434/0288/7322/files/asymptotes_of_a_curve.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/birizakidunupujudexi.pdf
    • https://cdn.shopify.com/s/files/1/0437/1618/2166/files/bazigar_novel_complete.pdf
    • https://cdn.shopify.com/s/files/1/0434/6665/3858/files/goletusid.pdf
    • https://cdn.shopify.com/s/files/1/0429/1880/5657/files/81002620810.pdf
    • https://cdn.shopify.com/s/files/1/0433/9128/7452/files/rutadosaxudejuzob.pdf
    • https://cdn.shopify.com/s/files/1/0432/6175/5547/files/zamemakif.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_off000045d0.bin
e011cb773a8aec632d310ebfa6313c78ceb92a3c07694dab80c4e78849f291ef
pdf-font-stream PDF embedded font (sfnt) at offset 0x45D0 5556 bytes
font_01_sfnt_off000058aa.bin
c4f1436bbc5fab5a9e8763fa31f33d34ef7b0cc87f2d2289c3d49de6ca5e70e2
pdf-font-stream PDF embedded font (sfnt) at offset 0x58AA 10660 bytes