Malicious PDF — malware analysis report

Static analysis result for SHA-256 bf4cec2694f75882…

MALICIOUS

PDF

76.1 KB Created: 2021-03-16 05:55:13 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-08-25
MD5: 2bf060234e8b69cb229f89557fe267b2 SHA-1: 2c1c6ae1d8aed67fbe7e6663de985c62bede7a47 SHA-256: bf4cec2694f7588295844c215e86c84c5e6e20530d259d62af704ba60f2aa51b
254 Risk Score

Malware Insights

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

The PDF contains numerous links, with a critical heuristic identifying it as a malicious redirector and a link farm. One of the primary redirector URLs is https://yafferge.ru/wix?keyword=the+three+b%2527s+of+classical+music, which is flagged as malicious. The ML classifier and ClamAV also strongly indicate maliciousness, consistent with a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • 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://yafferge.ru/wix?keyword=the+three+b%2527s+of+classical+music In PDF document text
    • https://vipagavufedolaz.weebly.com/uploads/1/3/5/3/135350232/d6ae3d.pdfIn PDF document text
    • https://mulunumidivopiz.weebly.com/uploads/1/3/5/3/135393794/pireludepopujusu.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://s3.amazonaws.com/selivuvumepaveb/62711034423.pdfIn PDF document text
    • https://s3.amazonaws.com/wovigebi/adagio_for_strings_viola_sheet_music.pdfIn PDF document text
    • https://s3.amazonaws.com/rowubunak/hoodie_template_vector_free.pdfIn PDF document text
    • https://s3.amazonaws.com/luworizesupox/mystery_brain_teaser_puzzles_metal.pdfIn PDF document text
    • https://s3.amazonaws.com/woberiz/aol_outgoing_mail_server_settings_android.pdfIn PDF document text
    • https://8641c524-1fb5-4292-87ed-dd72f64d6c22.filesusr.com/ugd/9b7d8a_3ccbddb051dd4be68333e006a2a12089.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nilititonawafim/jemisuxu.pdfIn PDF document text
    • https://s3.amazonaws.com/sajatofubote/33429738985.pdfIn PDF document text
    • https://s3.amazonaws.com/mukut/83687792577.pdfIn PDF document text
    • https://be934b08-0dcc-4e2e-8de1-c3c1c32dbfab.filesusr.com/ugd/d5415a_1f1b308b0f68476c9def10aede71b924.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/kavalukato/thank_you_letter_for_promotion_template.pdfIn PDF document text
    • https://2559d30b-64cd-4b4d-aaad-e76a675dde99.filesusr.com/ugd/f5a024_7de78cae085546e19d014827c537a524.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/zonebon/australasian_health_facility_guidelines_part_c.pdfIn PDF document text
    • https://1c92f6d8-19eb-429c-9239-1cf6be91372f.filesusr.com/ugd/cc1a03_b6929aa27f7049eb8f445efb2a0daee5.pdf?index=trueIn PDF document text
    • https://4e33067b-0f13-4bed-bb9c-ea95f768fd7c.filesusr.com/ugd/23924c_234c8404fa4b46be8b85f478e65e2099.pdf?index=trueIn PDF document text
    • https://24d1f61b-f5c5-4d2f-8180-62589f44e8d8.filesusr.com/ugd/eed56f_2e9a76c558a94115b895d83fac951742.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/tarizirefevifab/modern_engine_blueprinting_techniques.pdfIn PDF document text
    • https://334e481f-4595-4613-8514-cf1b68b0f675.filesusr.com/ugd/a5bb32_b3bfd0165e7c4867997b93b4f1e5e23c.pdf?index=trueIn PDF document text
    • https://s3.amazonaws.com/nijosinizo/nuvipawik.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_off0000ecae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECAE 5244 bytes
SHA-256: 6f4d3f32961c104e0e7c42ca401f748f1381f6f1c64e68d66b33019d47d524f1
font_01_sfnt_off0000fe62.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE62 10756 bytes
SHA-256: 322a8c7e41d0b22fced0df1ad7aa37cf6d1fe38360368c44c60adb8fb647ae5b