Malicious PDF — malware analysis report

Static analysis result for SHA-256 182c01d64e5e2ce2…

MALICIOUS

PDF

46.6 KB Created: 2020-07-13 23:32:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-04
MD5: b2b4e307733f25ee0a5ec22a7b0b9f66 SHA-1: 1208f691fb82c4bc85bed2fe6053bbe782b383b4 SHA-256: 182c01d64e5e2ce230416d653159a888a97caf0e578deefd83905105fceb5b34
254 Risk Score

Malware Insights

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

The PDF contains numerous links to redirector infrastructure, specifically `https://ttraff.cc/wb?keyword=free%20french%20grammar%20worksheets%20pdf`, which is flagged as malicious. The presence of a large number of external PDF links, many pointing to benign WordPress sites but some to unknown hosts, suggests an attempt to obscure the final malicious destination. ClamAV detection as `Pdf.Dropper.Agent-9528081-0` and ML classification further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • ClamAV: Pdf.Dropper.Agent-9528081-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Dropper.Agent-9528081-0
  • 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.cc/wb?keyword=free%20french%20grammar%20worksheets%20pdf In PDF document text
    • http://files.thenottinghamfour.com/uploads/1/3/2/7/132710628/91040fee.pdfIn PDF document text
    • http://files.fanhubnw.com/uploads/1/3/2/8/132815118/moxekiwaniguf.pdfIn PDF document text
    • http://files.doulababes.com/uploads/1/3/1/3/131380598/5934a67b.pdfIn PDF document text
    • http://files.lacharite.net/uploads/1/3/1/3/131380107/nesapa_sufagasawo_zogujodabujag.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://xawoluvega.files.wordpress.com/2020/07/juzumeloxir.pdfIn PDF document text
    • https://texamepup.files.wordpress.com/2020/06/24850818644.pdfIn PDF document text
    • https://pufifupafur.files.wordpress.com/2020/07/86701682941.pdfIn PDF document text
    • https://rilejeselu.files.wordpress.com/2020/06/wagonon.pdfIn PDF document text
    • https://dafowamu.files.wordpress.com/2020/06/41377131919.pdfIn PDF document text
    • https://kegozifidido.files.wordpress.com/2020/06/zafanajexanufekiguf.pdfIn PDF document text
    • https://xakafuwi.files.wordpress.com/2020/07/12688435097.pdfIn PDF document text
    • https://sivobir.files.wordpress.com/2020/07/xexaruxomunufa.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/pesaveput.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/9969/2958/files/gudomewuledoviripabove.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9485/2252/files/53484299084.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/30812088679.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/0123/4076/files/jamasefu.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/0555/8436/files/fixokifomodogagedutasave.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/9242/6405/files/werox.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_off000078f7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x78F7 5388 bytes
SHA-256: c94d3cd1e94405daa21e730b088c68e0a0d937d2f65d67220f128782716d940f
font_01_sfnt_off00008b28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8B28 9996 bytes
SHA-256: 7386dcc6e813a149476e5052622c8d95e76bf9282714c039a5b531d19dec7782