Malicious PDF — malware analysis report

Static analysis result for SHA-256 b2472a6d0e494cec…

MALICIOUS

PDF

61.3 KB Created: 2020-12-07 23:04:59 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: d2986668489eecc72d1886628a59fceb SHA-1: bd9e16674bda1a95c6b1018b6a81ac48aa7dbdda SHA-256: b2472a6d0e494cec61ea1f4d6a44a69eac95c5c9e6626dac52621bafe211df30
216 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by multiple heuristics as malicious, including brand-impersonation credential phishing for Outlook. It contains a large number of external links, many of which point to potentially malicious or SEO-spam content. The primary lure appears to be a fake worksheet answer key, directing users to a redirector URL that ultimately leads to a phishing page.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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.
  • Brand-impersonation credential phishing lure critical SE_BRAND_CREDENTIAL_PHISH
    Document impersonates a well-known consumer brand and uses account-security / verification language ('unusual activity', 'account on hold', 'verify your account') to steer the reader to a credential-harvesting link. Corroborated by: action link to abused redirector https://nujetamewude.weebly.com/uploads/1/3/4/8/134881912/rawexar.pdf.
  • 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://traffset.ru/123?utm_term=slope+and+similar+triangles+worksheet+answer+key PDF link annotation
    • https://nujetamewude.weebly.com/uploads/1/3/4/8/134881912/rawexar.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4476590/normal_5fbccf4ac3556.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4409110/normal_5f94db5b53110.pdfIn PDF document text
    • https://xaweworamek.weebly.com/uploads/1/3/4/6/134610398/badfa92fcab.pdfIn PDF document text
    • https://latudawa.weebly.com/uploads/1/3/4/3/134308630/5735803.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4403563/normal_5fa129cd52496.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4501503/normal_5fad5a2cd5cab.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4379601/normal_5fc3746acad99.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/mefonevimimix/asilomar_ai_principles.pdfIn PDF document text
    • https://s3.amazonaws.com/dufekifaral/5_south_african_based_food_dietary_guidelines.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/78b142ad-018e-48aa-9e8d-101cde8fd9e2/sabizivagagusanenof.pdfIn PDF document text
    • https://s3.amazonaws.com/wunupalezozerud/bobibaromadalipawu.pdfIn PDF document text
    • https://s3.amazonaws.com/tesotiwapax/favatewufimomepizew.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_off0000b2c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2C5 5736 bytes
SHA-256: 24f20765bea3c81209b81e4d629a9de192cb53654de903c5f1acd9afdca27d7f
font_01_sfnt_off0000c633.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC633 10012 bytes
SHA-256: 99d3a20d9b162eb7c6793d70c13bd8080ba99ad3b47e17ae84b46edeeedd1ec5