Malicious PDF — malware analysis report

Static analysis result for SHA-256 2b8561810881b505…

MALICIOUS

PDF

78.3 KB Created: 2021-09-11 23:57:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: c85787a95882c29ff0c415281b5c6576 SHA-1: 770dda2157eb77846ff35e4e9d074c4654edfaa8 SHA-256: 2b8561810881b505a609dab6157a366d074c03cd7b5e6dad95c950c351975f0a
142 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript, a common technique for executing malicious code within documents. The presence of numerous external URIs, many pointing to potentially disposable domains and flagged as a link farm, suggests a phishing or scam attempt to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to download and execute a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 7

  • 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 is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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 http://mxag.com/upload/browse/file/73405806035.pdf In PDF document text
    • http://dezis.ru/uploads/files/36389741293.pdfIn PDF document text
    • http://gamebonda.com/ckupload/files/kagepufubozud.pdfIn PDF document text
    • http://deleersnijder-bocaege.be/images/file/81193937260.pdfIn PDF document text
    • http://cuatro-pr.org/sites/default/files/file/rereroduzu.pdfIn PDF document text
    • http://www.gonouvellezelande.com/files/29875731899.pdfIn PDF document text
    • http://studiotecnicomaglio.it/userfiles/files/11362368551.pdfIn PDF document text
    • http://www.kickcommerce.com/userfiles/file/zodofugefodamed.pdfIn PDF document text
    • http://quimis.org/js/ckfinder/userfiles/files/393949260.pdfIn PDF document text
    • http://crescentcarpets.com/userfiles/file/20298457000.pdfIn PDF document text
    • http://jaatkinson.com/userimages/98662107165.pdfIn PDF document text
    • http://bukhatirhomes.com/userfiles/file/24673159803.pdfIn PDF document text
    • https://www.pharmawell.eu/ckfinder/userfiles/files/tekopupodazixasofil.pdfIn PDF document text
    • http://mediedil.eu/userfiles/files/rudebizaniwupug.pdfIn PDF document text
    • https://telliogluhukuk.com/userfiles/file/latizulopofafavezivivep.pdfIn PDF document text
    • https://jagamimpi.com/contents/files/tabejimaf.pdfIn PDF document text
    • https://lodoshosting.com/calisma2/files/uploads/monejeburisotamexukolobo.pdfIn PDF document text
    • http://tbeaindia.com/userfiles/file/16845706871.pdfIn PDF document text
    • https://ethnicminorities.heephong.org/ethnicminorities/cmsadmin/ckfinder/files/jusumiwozalased.pdfIn PDF document text
    • http://zabbeleecooking.com/ckfinder/userfiles/files/70413239958.pdfIn PDF document text
    • http://medwin.kr/userData/board/file/15339257092.pdfIn PDF document text
    • https://searchlink.org/userfiles/file/87546473412.pdfIn PDF document text
    • http://a-pluset.com/userfiles/mobetiz.pdfIn PDF document text
    • https://at-studio.tw/app/webroot/userfiles/files/20210904_233253.pdfIn PDF document text
    • http://floramarble.com/uploads/vomegarelavolizovu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=underrated+multiplayer+games+pcPDF link annotation
    • 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://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000cd58.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCD58 17408 bytes
SHA-256: 1a62fb3e9350f1ac47b2f337a47b458fccfe7612e6134bf03eead8baca1959ad
font_01_sfnt_off0000fa56.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA56 10960 bytes
SHA-256: ee3f0111d8018629886884fea424f0d5ec98eb0faceb5054c913ac18b6facb93
font_02_sfnt_off0001137f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1137F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1