Malicious PDF — malware analysis report

Static analysis result for SHA-256 f89ad0573ace6e65…

MALICIOUS

PDF

78.7 KB Created: 2021-03-18 15:10:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 8c7306f1aff53020a3f2e8d526b7b494 SHA-1: da876209f776cfc64dc460b6cf3a0a01249f7113 SHA-256: f89ad0573ace6e65b07b6bdb6ed1f90e214b1871a76ac1e0a2ac08a5a4755623
196 Risk Score

Malware Insights

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

The PDF contains numerous external links, many of which point to SEO-optimized URLs designed to redirect users. One prominent URL, 'https://pelibifir.ru/strik?utm_term=learn+english+grammar+for+beginners+pdf', is identified as a redirector. The presence of a PDF link farm and the ML classification strongly indicate malicious intent, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://pelibifir.ru/strik?utm_term=learn+english+grammar+for+beginners+pdf PDF link annotation
    • https://cdn.sqhk.co/jomububorava/ijpCReJ/sirolimus_cost_with_insurance.pdfIn PDF document text
    • http://sejerodetupumil.medianewsonline.com/where_are_the_batteries_in_a_older_swiffer_wet_jet.pdfIn PDF document text
    • http://melofuwi.getenjoyment.net/36665896937.pdfIn PDF document text
    • https://cdn.sqhk.co/koxajavu/cq4KhbW/73169226341.pdfIn PDF document text
    • https://cdn.sqhk.co/zogameva/cWDjg1c/30632817491.pdfIn PDF document text
    • http://nomudepalak.medianewsonline.com/26133607935.pdfIn PDF document text
    • https://cdn.sqhk.co/duravukikemo/gZif4gc/supedunijupesadetifok.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://s3.amazonaws.com/zuwimadaneb/brothers_full_movie_hotstar.pdfIn PDF document text
    • https://s3.amazonaws.com/jivamubug/massachusetts_appeals_court_case_information.pdfIn PDF document text
    • https://s3.amazonaws.com/wunojipu/how_to_have_multiple_sources_of_income_in_india.pdfIn PDF document text
    • https://5b0e1d79-1acc-45ba-a965-31015372eee8.filesusr.com/ugd/67f5f7_cdd8ad671bcd495187f55f2edee29735.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/jezaxojipevu/form_a_b_c_d_format.pdfIn PDF document text
    • https://6e345194-e688-4037-aa24-2ff230a16836.filesusr.com/ugd/ce9fe1_2b7c12c1da314451949ede79d7d7a9b6.pdf?index=trueIn PDF document text
    • https://764dfaed-7091-4b1c-a8ff-ceb5b694923f.filesusr.com/ugd/4bafdb_f7eb7020e5a54a199ea6b164389701a3.pdf?index=trueIn PDF document text
    • http://titasukutisun.epizy.com/nakisizi.pdfIn PDF document text
    • http://kusababi.onlinewebshop.net/jidisakaruris.pdfIn PDF document text
    • https://s3.amazonaws.com/wizidimawag/volopamaxefaruvad.pdfIn PDF document text
    • http://zuwapiw.rf.gd/bajifatobodifamati.pdfIn PDF document text
    • http://saxuwomepeboke.epizy.com/lapuzisuzopepi.pdfIn PDF document text
    • http://dokudaruriwiv.atwebpages.com/2005_buick_lacrosse_cxl_reviews.pdfIn PDF document text
    • https://a6132035-7465-4fe4-be4e-2faa96c22dab.filesusr.com/ugd/cf950b_f99bb0b144a04879bb82619237355bfa.pdf?index=trueIn 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 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e78b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE78B 5244 bytes
SHA-256: 083f1074740cbf2b0a8e21d1310b59820b7e9d9cef5db043e7eaec835f34f61f
font_01_sfnt_off0000f922.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF922 11568 bytes
SHA-256: 658a5b6bd058d99510758a419ccaf0865e5d889f25db54daca8d4923493b1fde
font_02_sfnt_off00011f52.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F52 4324 bytes
SHA-256: 0d0f64e27578eb124b8bc81c7eceacdd166e22eddd95c81328e9fbd7de2a6333