Malicious PDF — malware analysis report

Static analysis result for SHA-256 637a92066d5f56cf…

MALICIOUS

PDF

52.2 KB Created: 2020-08-10 20:33:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-07
MD5: 200b619fbebb6c332a3dcd02e8e260fc SHA-1: 5f48a55bd6625708baa1c32c37c2364ef02f1c8a SHA-256: 637a92066d5f56cfa44ce499488914e19e4a31879db075cfba6b53fce75077f6
194 Risk Score

Malware Insights

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

The PDF contains numerous links designed to appear as legitimate downloads, but they redirect to a known malicious infrastructure. The ML classifier strongly indicates maliciousness, and the PDF structure suggests a link farm for SEO-based phishing. No scripts were extracted, but the embedded links are the primary threat.

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.ru/pify?keyword=mathematical+economics+books+pdf In PDF document text
    • http://files.pumpernickelpictures.com/uploads/1/3/1/3/131398109/7733719.pdfIn PDF document text
    • http://files.benjaminyeo.com/uploads/1/3/1/4/131438397/06aebc5ef71c.pdfIn PDF document text
    • http://files.keytoyourhomeph.com/uploads/1/3/0/8/130813409/fepaxinorenofa.pdfIn PDF document text
    • http://files.michaelwarrenmurphy.net/uploads/1/3/1/4/131454012/regezewowif-wofenur-puvuvinaveloxi-vugim.pdfIn PDF document text
    • http://files.sydneyschiffdanceproject.com/uploads/1/3/2/6/132682739/ad45d3bb001d.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/3183/0421/files/magesovekixojogarekebe.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/9426/9333/files/79273624230.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/4267/6636/files/12824150008.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/8383/3249/files/18888004723.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/1393/0142/files/96610471297.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0435/4162/7029/files/adobe_acrobat_reader_dc_scan_to.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/8230/1094/files/leroloxufafuras.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/7514/1783/files/vurobuwiroriloxip.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/5433/3093/files/razerisupupuweteju.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/4398/7361/files/ms_paint_download.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/3337/9487/files/penguin_reader_level_4_download.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/5639/7464/files/sunomopu.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_off00008f01.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8F01 5508 bytes
SHA-256: 49cf8252d64ca3e220209346ed70e140883d538d24d5455374ad9c0ab065fbdd
font_01_sfnt_off0000a198.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA198 9908 bytes
SHA-256: 1058fa933d053db94adf72ce4324fecd5e04ac0413b407ffe45f9cb266929afc