Malicious PDF — malware analysis report

Static analysis result for SHA-256 899858df7e5ecf21…

MALICIOUS

PDF

50.7 KB Created: 2020-08-22 09:05:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2026-05-08
MD5: 977403ebef2cdeebb5a605186316dd11 SHA-1: a1b67aed31a27dad4337abae207d5294f0047a87 SHA-256: 899858df7e5ecf21f4e0392593f72946e25108b9ae6334e85fc2fb6e69bf110c
194 Risk Score

Malware Insights

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

The PDF contains a link to a redirector, which in turn points to a purported free adblocker browser APK. This suggests a phishing or potentially unwanted software distribution scheme. The ML classifier strongly indicated maliciousness, and the presence of numerous links points to a link farm or SEO abuse tactic to drive traffic to the malicious redirector.

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=free+adblocker+browser+advanced+mode+apk In PDF document text
    • http://files.centrocha.org/uploads/1/3/0/8/130873870/7918256.pdfIn PDF document text
    • http://files.bexleyvoice.org.uk/uploads/1/3/0/7/130776343/sufamimosivaki.pdfIn PDF document text
    • http://nafizeb.frhsmusical.com/uploads/1/3/1/3/131381241/8ca4bb9ef1c.pdfIn PDF document text
    • http://files.facundomenendez.com/uploads/1/3/1/4/131438137/puxugurudu.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/1/0432/8072/8224/files/43840374452.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/3519/7602/files/12305204961.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0436/9186/8313/files/american_dad_season_12_torrent.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0440/8963/9077/files/kufedasodusufasaj.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0440/4104/4118/files/wixejivijobujelimonudimaz.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0439/0112/4760/files/21458565152.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0435/1967/2472/files/55860745140.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/9558/8005/files/93745407666.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/1616/7328/files/brche_erweitern_aufgaben.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0438/5406/9925/files/85763741723.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/1613/4562/files/80343614778.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/1685/5457/files/39620672292.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/5444/8286/files/zufajofuvidalilupax.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0437/5108/0087/files/rental_agreement_format_bangalore.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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00006488.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6488 5532 bytes
SHA-256: 4bea8945fc7d2e2e652543139505c9ecbd68348179451af1fd095febc52ca483
font_01_sfnt_off0000774a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x774A 2448 bytes
SHA-256: 6a486ef7ee7746d00a38320c3335a15c9f0a2e49e60a64a1e9cfa8d54586f514
font_02_sfnt_off000080fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x80FA 10844 bytes
SHA-256: f32b7e655421197180e6cfa282d252cf29dfe366872329a5cce826fd582c6851
font_03_sfnt_off0000a5ba.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA5BA 16212 bytes
SHA-256: ad0114a8f0d67067cfd4860469879bdd9774b44daae9d88c9bc32f9414120ad3