Malicious PDF — malware analysis report

Static analysis result for SHA-256 6a50bbc26ac51518…

MALICIOUS

PDF

59.2 KB Created: 2020-09-11 05:49:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: f7a332013fa5083d4b97438714bcdffb SHA-1: 581b4b63782cfc99127f9f85c22ae4942ca310d3 SHA-256: 6a50bbc26ac515180c60eb72b953d822ad7d03bc2cc8a38d01806ca9013b4666
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains a heuristic firing for a malicious redirector link, pointing to 'https://ttraff.me/wix?keyword=what+is+chiari+malformation'. Additionally, it exhibits characteristics of a PDF link farm, embedding a large number of external PDF links, with 'https://static.usrfiles.com/ugd/bdeb4c_ba154473300743f58ba9d4c4d81a6eda.pdf' being the first identified. The ML classifier also flagged this PDF as malicious with high confidence. The document body, though partially corrupted, contains the malicious URL and other PDF links, suggesting a lure to external content.

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.me/wix?keyword=what+is+chiari+malformation
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://static.usrfiles.com/ugd/bdeb4c_ba154473300743f58ba9d4c4d81a6eda.pdf
    • https://static.usrfiles.com/ugd/1a89c8_7248255654824e209fbfbabf886446e0.pdf
    • https://static.usrfiles.com/ugd/6cfc61_364f595cab354863b4572096383ead47.pdf
    • https://cdn.shopify.com/s/files/1/0431/8589/7627/files/feliz_navidad_piano_sheet_music_free.pdf
    • https://cdn.shopify.com/s/files/1/0435/2599/6698/files/gepogosunu.pdf
    • https://cdn.shopify.com/s/files/1/0441/3777/5256/files/83941746106.pdf
    • https://cdn.shopify.com/s/files/1/0432/2004/1886/files/wamojisi.pdf
    • https://cdn.shopify.com/s/files/1/0429/8699/5863/files/7436695596.pdf
    • https://cdn.shopify.com/s/files/1/0431/0528/8352/files/aristocrat_technologies_company_information.pdf
    • https://cdn.shopify.com/s/files/1/0434/2480/9122/files/alternating_current_physics_notes.pdf
    • https://cdn.shopify.com/s/files/1/0435/9146/7176/files/21963672222.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ab0e.bin
eb6addc53b5d932163d2904d0cd543cedb5752d4b31d544d35b78471d15ca1d4
pdf-font-stream PDF embedded font (sfnt) at offset 0xAB0E 5136 bytes
font_01_sfnt_off0000bc65.bin
8533b55f286f61e782eec915815539ecc920a566d7f3161b4c8a5fce52b2aaf0
pdf-font-stream PDF embedded font (sfnt) at offset 0xBC65 10624 bytes