Malicious PDF — malware analysis report

Static analysis result for SHA-256 befdb9d0f856971c…

MALICIOUS

PDF

49.0 KB Created: 2020-07-14 21:22:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-04
MD5: ba0af94bb2d7cf6f46662b883c27a158 SHA-1: 8c5c2b9290f8a1de39c0572250f18fd62a0f2b81 SHA-256: befdb9d0f856971c2c8569ad20284f8f4aff73afc3ab6d411cf0c5e0adc48f6d
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.001 Malicious Link T1059.001 PowerShell

The PDF contains a large number of external links, many of which point to WordPress hosted PDFs, indicating a link farm for SEO poisoning. One critical heuristic firing confirms a link to known malicious redirector infrastructure at 'ttraff.cc'. The ML classifier also strongly flagged this PDF as malicious. No scripts were extracted from this sample.

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.cc/wb?keyword=change%20noun%20to%20adjective%20list%20pdf In PDF document text
    • http://files.beechtreecustomcabinets.com/uploads/1/3/1/4/131453245/jaxorapabamozu.pdfIn PDF document text
    • http://files.sriyantra.com/uploads/1/3/2/7/132740384/lapuvezono_terigijazarod_difuvodoxejajo_wadifiz.pdfIn PDF document text
    • http://files.edenfarms.net/uploads/1/3/1/8/131857679/gerusevufibolutosuka.pdfIn PDF document text
    • http://files.manchesteradp.com/uploads/1/3/0/7/130775737/7651316.pdfIn PDF document text
    • http://files.factorfakedfan.com/uploads/1/3/0/9/130969572/vojuriwusomoparut.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://pemasedolo.files.wordpress.com/2020/07/22630438461.pdfIn PDF document text
    • https://zibebutekura.files.wordpress.com/2020/07/zosokonifoloxeguxikezi.pdfIn PDF document text
    • https://gukubulori.files.wordpress.com/2020/07/86875125906.pdfIn PDF document text
    • https://josejoxoboko.files.wordpress.com/2020/06/74396145625.pdfIn PDF document text
    • https://govorif.files.wordpress.com/2020/07/73132847694.pdfIn PDF document text
    • https://warezofokel.files.wordpress.com/2020/07/modimawekuzoduwutuvuder.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/xubeke.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/25424470269.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/6769/5509/files/80419016569.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/3749/1357/files/38613912053.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/6647/5174/files/19382844652.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/87967576867.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/2849/6036/files/wobelalapevoxusenagepima.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/2717/7380/files/8885457184.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/6633/6167/files/pafuverima.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_off00007b1d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7B1D 5364 bytes
SHA-256: 9693ab0f315c8881d82a1f83c1b3eb8b2512c2e253d41ba860049b4a6e73d83e
font_01_sfnt_off00008d6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8D6D 12880 bytes
SHA-256: fc0d2d26dc2ff59790952e1458b325b1c6edece8fe349b897f499079c38ef8ba