Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4792817a27c9c7e…

MALICIOUS

PDF

76.9 KB Created: 2021-09-24 08:35:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 7bff6ed961a8db172f263c5de20e36e0 SHA-1: edf23efff0f4bdac7a47538e1b69164d2c46c252 SHA-256: a4792817a27c9c7e971d1938e848b1a9d33c6d7d6f7deb0bad2eb262ef4e4ade
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm pointing to compromised CMS uploads and disposable hosting, suggesting a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the presence of multiple external URIs and the nature of the heuristics strongly suggest an attempt to redirect the user to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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 link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • 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.
  • 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://mayxaydunghoangphuc.com/userfiles/files/wulemurop.pdf In PDF document text
    • http://progfin.pl/userfiles/file/73248229059.pdfIn PDF document text
    • http://haiqi-machine.com/d/files/wipegaruxu.pdfIn PDF document text
    • http://nobody-films.com/bpms/includes/fckeditor_uploads/userfiles/file/debadakemoxiniv.pdfIn PDF document text
    • http://transporteslaplata.com/imagenes_web/file/fowunufad.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b38239ac69---99507457635.pdfIn PDF document text
    • http://amindoost.ir/images/upload/files/basibuwuwo.pdfIn PDF document text
    • http://osteriadelcampanile.com/userfiles/files/22417943699.pdfIn PDF document text
    • http://plncse.hu/php_data/file/basevotin.pdfIn PDF document text
    • https://thietbixanh.net/uploads/files/14267118927.pdfIn PDF document text
    • https://grandiosieventinuziali.it/filesUploads/file/wazawasivonawowasadofek.pdfIn PDF document text
    • https://ienter.bg/files/20951667251.pdfIn PDF document text
    • http://karaokejdi.com/ckfinder/core/connector/php/upload/files/78309945257.pdfIn PDF document text
    • http://neoneofitou.com/ckfinder/userfiles/files/degifolijelujekuk.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/056ba1f0cb81f6d7f90892cdbfeeebe0/mesijikukewefaride.pdfIn PDF document text
    • http://ourgans.org/userfiles/files/18840393706.pdfIn PDF document text
    • http://scea.edu.mn/ckfinder/userfiles/files/37537316519.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614b69b2e8926---daxixeje.pdfIn PDF document text
    • http://kadh.kr/bobod/upload/file/loboritimagoladofalosi.pdfIn PDF document text
    • https://bluetact.com/ckfinder/userfiles/files/14321410568.pdfIn PDF document text
    • https://habibitoursegypt.com/ckfinder/userfiles/files/39313536554.pdfIn PDF document text
    • http://naturallabs.fr/userfiles/file/96499591869.pdfIn PDF document text
    • http://www.udelimpa.es/ckfinder/userfiles/files/buzojitoragokodidut.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/LPIa9PGmDLg/uplcv?utm_term=lucky+day+mod+apk+2020PDF 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_off0000c60d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC60D 18216 bytes
SHA-256: 32315ffd0b42f060542aef34653a11037bf6be9b28ed9c0e553b83eb9b054250
font_01_sfnt_off0000f62b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF62B 10440 bytes
SHA-256: 357c78780121ad8ccc3bb1cdf4133c6050f8acfee99289a4dd06f31b0ed806c1
font_02_sfnt_off00010df4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DF4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1