Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e6df5cd3d90c38c…

MALICIOUS

PDF

44.9 KB Created: 2020-07-17 10:42:00 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-04
MD5: a22127a6dc9e39d534c532250cf36001 SHA-1: 242f8846b5cf610df220257f7c3d044bc0051dfa SHA-256: 3e6df5cd3d90c38c813485fb90031c7508215efc6d78ecd48ef17cfde91224d6
194 Risk Score

Malware Insights

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

The PDF contains embedded links that redirect to malicious infrastructure, as indicated by the PDF_MALICIOUS_REDIRECTOR_LINK and PDF_SEO_LINK_FARM heuristics. The document body, though heavily obfuscated, suggests a lure related to file conversion. The ML classifier also strongly flagged this PDF as malicious. The primary attack vector appears to be directing users to external malicious sites via a link farm.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • 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.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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.com/wb?keyword=convert%20jpg%20to%20pdf%20below%20200kb In PDF document text
    • http://files.thetlacademy.shop/uploads/1/3/1/3/131384789/dupive-madelubupazape-dezarekinoza.pdfIn PDF document text
    • http://files.robyntillman.com/uploads/1/3/1/0/131070754/sepupapudi_foxubebarale_degiv_letapik.pdfIn PDF document text
    • http://files.barbadiancanadians.com/uploads/1/3/1/6/131607063/balukufitub.pdfIn PDF document text
    • http://files.gigharborcruisers.com/uploads/1/3/1/6/131607010/11da83.pdfIn PDF document text
    • http://files.virvahinnemo.com/uploads/1/3/2/6/132682897/dabd6f3d12.pdfIn PDF document text
    • http://files.drummondsmedlegal.com/uploads/1/3/1/0/131071209/9cf8efad25c11.pdfIn PDF document text
    • http://files.antoniasellbach.com/uploads/1/3/1/8/131871467/7504635.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://lejobadoni.files.wordpress.com/2020/06/takaborerizenaduxusapulad.pdfIn PDF document text
    • https://tumezup.files.wordpress.com/2020/07/jufizol.pdfIn PDF document text
    • https://fupiwexobus.files.wordpress.com/2020/07/55524376421.pdfIn PDF document text
    • https://gopisasiru.files.wordpress.com/2020/07/85968894219.pdfIn PDF document text
    • https://gopixur221482700.files.wordpress.com/2020/07/nibolizipat.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/4329/9234/files/tobunavazewevasode.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/3921/9099/files/rurunovexiladuvin.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/31968244380.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/7243/7910/files/tufesaza.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/6901/4177/files/44158936185.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/8992/9116/files/63324743552.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/8585/6919/files/1142719999.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/lokilus.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00007064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7064 5292 bytes
SHA-256: 5cfe3b9a84fc173201ecb1bff47e5cf54636c26b821bc3bd119cb2e3c851b91a
font_01_sfnt_off0000829b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x829B 10488 bytes
SHA-256: bc78d9d7f3067032c495114290f1a1d0e8c1c8e3e74daa8a96c10b0b441c32ab