Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8f9b3e4c481c7ca…

MALICIOUS

PDF

39.2 KB Created: 2020-08-08 22:17:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-09
MD5: b500f2830f994c1c97b6fe58ec7fa7ee SHA-1: e8f06ded97947d420ae9a7c003bc14eb3963dfd8 SHA-256: b8f9b3e4c481c7ca81d4e8d8713956bce00e45bcc270f0e1db890ac10ab9d8ef
194 Risk Score

Malware Insights

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

The PDF contains a mass of external links, many of which are hosted on Shopify, but one specific link points to a known malicious redirector. The document body, though heavily obfuscated, contains the text 'Algebra ii worksheets pdf' and the malicious URL, suggesting a lure to trick users into clicking the link. The ML classifier also strongly indicated maliciousness.

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/pify?keyword=algebra+ii+worksheets+pdf In PDF document text
    • http://files.spurwing-ebooks.com/uploads/1/3/0/7/130776001/tamuxutixopojiw.pdfIn PDF document text
    • http://files.anzaborregopaleo.org/uploads/1/3/1/4/131437246/83768c05.pdfIn PDF document text
    • http://files.superiorclinics.com/uploads/1/3/2/8/132816066/9419717.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/1/0428/4288/2215/files/suwesugelin.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/2674/2421/files/mavovekude.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/7113/6154/files/19656576434.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/3622/9278/files/international_arbitration_act_15_of_2020.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0458/3318/files/30447141788.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0435/8311/1323/files/intro_to_heat_transfer_6th_edition.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/3350/9534/files/jerek.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/7430/6719/files/xufojekadepu.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/7727/1706/files/26935438800.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/1775/7095/files/estomatitis_aftosa_nios.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/mulobovapu.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0440/5913/2056/files/list_of_words_with_prefixes.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/6406/6209/files/jivesokomidominulafisiw.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0440/3943/8486/files/enterprise_risk_management_thesis.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_off00005ac5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5AC5 5588 bytes
SHA-256: 45f13d2fdd121b4ab0dd958e4ce24c9cb5434101019017831f5ec29259eae753
font_01_sfnt_off00006dcd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6DCD 10008 bytes
SHA-256: 98559cd87f26fe194b5747414215ccc8f3903f53fbd4b84cf2bcd18f00130baa