Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8f9caf04403a1be…

MALICIOUS

PDF

34.6 KB Created: 2020-08-13 12:16:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 11c4ceef819fab13620c023df31dd363 SHA-1: a49e561d128113430d461307d0d40ed785ca0495 SHA-256: f8f9caf04403a1be802ffce205753a1ea13c123c71b01904e4c2fabe8f35939f
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, with a critical heuristic firing for PDF_SEO_LINK_FARM indicating a link farm. One of these links, https://ttraff.ru/wb?keyword=aleluia%20a%20minh'alma%20abrirei%20partitura%20pdf, is flagged as a malicious redirector. The document body, though heavily obfuscated, contains references to the same URL and other Shopify-hosted PDFs, suggesting a coordinated effort to drive traffic to malicious infrastructure. The ML classifier also strongly indicated maliciousness.

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=aleluia%20a%20minh
    • http://dabusu.conservatoryathome.com/uploads/1/3/2/8/132814989/1285634.pdf
    • http://files.jonathandearmusic.com/uploads/1/3/2/3/132303359/9ec48265ab860.pdf
    • http://files.huronlandscape.com/uploads/1/3/1/6/131637928/0db09038b736.pdf
    • https://cdn.shopify.com/s/files/1/0433/1002/2814/files/golitiwizanakosodogomodux.pdf
    • https://cdn.shopify.com/s/files/1/0433/1339/7924/files/posoguvokemik.pdf
    • https://cdn.shopify.com/s/files/1/0431/9143/5422/files/91585774984.pdf
    • https://cdn.shopify.com/s/files/1/0434/2117/1864/files/poulin_chainsaw_manual.pdf
    • https://cdn.shopify.com/s/files/1/0428/8679/1334/files/clip_studio_paint_crack.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/zobirunutopuwipigodilig.pdf
    • https://cdn.shopify.com/s/files/1/0432/2797/1741/files/bass_guitar_learning_book.pdf
    • https://cdn.shopify.com/s/files/1/0438/1740/2530/files/kosarevuvaleroju.pdf
    • https://cdn.shopify.com/s/files/1/0427/4470/9276/files/bengali_biography_books_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0432/0192/1184/files/35481506884.pdf
    • https://cdn.shopify.com/s/files/1/0434/3191/9765/files/31626516013.pdf
    • https://cdn.shopify.com/s/files/1/0438/8097/2456/files/new_year_bulletin_board.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_off0000476b.bin
d0b709310d8e8b58132eddfbd460cca01e0226b7fef56047c7b63926d7314831
pdf-font-stream PDF embedded font (sfnt) at offset 0x476B 5268 bytes
font_01_sfnt_off00005922.bin
9bcf99173e04a69387e43f1b3399f33cb8cfe5e40faa7e3c1275d81ef2bce21a
pdf-font-stream PDF embedded font (sfnt) at offset 0x5922 10404 bytes