Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef8718ffc73884a8…

MALICIOUS

PDF

42.0 KB Created: 2020-08-11 08:08:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-07
MD5: 18aced02a59f5fb862594ce2ac360484 SHA-1: a3ec518fd32109391fa120cdd675112febea1148 SHA-256: ef8718ffc73884a83281d77624a5107ae04c4065bc4f0caed935042f590f657d
194 Risk Score

Malware Insights

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

The PDF contains numerous links to external resources, with one critical heuristic identifying a link to a known malicious redirector. The document body, though malformed, contains the text 'Conjunctions in english exercises pdf' and the malicious URL, suggesting a lure to trick users into clicking the link. The presence of a link farm further indicates a malicious intent to drive traffic to potentially harmful sites.

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/pify?keyword=conjunctions+in+english+exercises+pdf In PDF document text
    • http://files.specialedu4parents.com/uploads/1/3/1/6/131606368/liwatinemi.pdfIn PDF document text
    • http://files.nextstepsphysio.co.uk/uploads/1/3/0/8/130874493/lubesetos.pdfIn PDF document text
    • http://files.bigtrecreation.com/uploads/1/3/1/3/131379612/fasezojozixuf.pdfIn PDF document text
    • http://files.outoftheboxphotography.net/uploads/1/3/1/1/131164112/7a3bead1f7932e.pdfIn PDF document text
    • http://files.zilzaladrums.com/uploads/1/3/1/4/131407144/bobebegejeroniku.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/1/0435/9186/0379/files/pupebejepagixebodokiweme.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0436/2259/6768/files/1861342060.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/8977/2187/files/67651039674.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/9238/5700/files/57745581316.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/0508/2781/files/33847699372.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/8900/2645/files/xidadigugovulivijej.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/3801/4616/files/99129835049.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/2978/1918/files/7470071465.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/87745409623.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/fuxojusi.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/4957/3784/files/aide_mmoire_mathmatique_secondaire_1.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0439/5424/1694/files/xabugaxujupe.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/1739/5614/files/falodirudevetivujifobafow.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_off00006676.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6676 5256 bytes
SHA-256: 9e3331a96943dc9f4d727e26537fdd3ca74c1d1ccfceb7b8a73615d41ba555bd
font_01_sfnt_off00007862.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7862 10144 bytes
SHA-256: 8f44e3a97ccfd32e2f21ec0ec097f31b06c654b42ebe92cc358c713774c23301