Malicious PDF — malware analysis report

Static analysis result for SHA-256 d4184d51c05d594e…

MALICIOUS

PDF

48.2 KB Created: 2020-08-02 04:40:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: cc8d556d21a6f8515e3d1cc6105fe6dd SHA-1: 657eb11f09d97f3ed6a1902035d023367d8fb82b SHA-256: d4184d51c05d594e4a816bed8ad5dfdc22beec556541f078930dda2ccafb46c6
152 Risk Score

Malware Insights

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

The PDF was flagged as malicious by an ML classifier and contains a large number of embedded links, indicating a link farm strategy. One of the embedded URLs, https://ttraff.ru/pify?keyword=git+remove+upstream+branch, is identified as a known malicious redirector. The document body itself is heavily obfuscated and contains metadata suggesting it was generated by wkhtmltopdf, but the primary malicious activity appears to be the distribution of numerous links.

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=git+remove+upstream+branch
    • http://files.onpointbuildersinc.com/uploads/1/3/2/7/132712040/b9fd32.pdf
    • http://files.startnetsystem.com/uploads/1/3/1/8/131856492/2848324.pdf
    • http://files.eastbudleigh.org.uk/uploads/1/3/1/4/131407465/zosedomopoliz.pdf
    • http://files.nataliedownes.com/uploads/1/3/1/8/131856435/4768287.pdf
    • https://cdn.shopify.com/s/files/1/0431/5283/4717/files/kukexefopi.pdf
    • https://cdn.shopify.com/s/files/1/0430/3070/8385/files/solomon_biology_10th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0433/3128/9256/files/jemevatijugixopevijak.pdf
    • https://cdn.shopify.com/s/files/1/0428/1604/5222/files/xokagoxenig.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/tozonolemudafolafoxi.pdf
    • https://cdn.shopify.com/s/files/1/0429/4891/9450/files/wagixawi.pdf
    • https://cdn.shopify.com/s/files/1/0430/0714/8185/files/acestream_to_chromecast.pdf
    • https://cdn.shopify.com/s/files/1/0429/8014/7359/files/kuwapadoxepidiroxapuwuso.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/41078692832.pdf
    • https://cdn.shopify.com/s/files/1/0434/1281/6039/files/65906346745.pdf
    • https://cdn.shopify.com/s/files/1/0437/2194/9335/files/tmux_kill_pane.pdf
    • https://cdn.shopify.com/s/files/1/0437/8440/5153/files/index_function_google_sheets.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_off0000704a.bin
6df59a06afffdab9629d98a1bc1093c283199c8f992402cff6a1e51b144e7e18
pdf-font-stream PDF embedded font (sfnt) at offset 0x704A 5372 bytes
font_01_sfnt_off00008267.bin
ef6ddf84ca768b6ad94f807625c1ab434203cabe977d19a5e66a641257572b30
pdf-font-stream PDF embedded font (sfnt) at offset 0x8267 18220 bytes