Malicious PDF — malware analysis report

Static analysis result for SHA-256 b5e61c837cb73b14…

MALICIOUS

PDF

82.1 KB Created: 2021-09-10 00:55:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 948165b4bba58583379ad7692dd39ff3 SHA-1: 1618fafee15c525dc5612a1307074f38801c60e9 SHA-256: b5e61c837cb73b1477e4218c7e0f877871d43f02b7fee122ce27ec84b6904b18
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. Heuristics indicate the document functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS uploads or disposable domains. The presence of numerous unknown URLs suggests an attempt to distribute malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 http://trieuduong.com/images/Download/berevofiboros.pdf In PDF document text
    • https://iieng.org/editor/ckfinder/userfiles/files/30254841125.pdfIn PDF document text
    • http://flomojapan.com/upload/files/muwibiponusugabumexun.pdfIn PDF document text
    • http://krajinar.cz/soubory/files/89359355281.pdfIn PDF document text
    • https://tradingcall.in/ckfinder/userfiles/files/49107554704.pdfIn PDF document text
    • https://dunaweb.co/bg_image/files/8498999255.pdfIn PDF document text
    • http://artechq8.com/beta/uploads/files/99696046907.pdfIn PDF document text
    • http://preciz.com/uploads/wysiwyg/files/92815789651.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/24a819ef0181e96673cc9a677226fd01/tutirerani.pdfIn PDF document text
    • https://stepweystudy.com/ckfinder/userfiles/files/65347469767.pdfIn PDF document text
    • http://licausi.it/userfiles/files/sexusigaserodiledunesep.pdfIn PDF document text
    • http://kfbma.org/files/fck/file/57073649313.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161373f08f3afe---vesikokegalutidofelin.pdfIn PDF document text
    • http://weorderfood.com/uploads/files/sezomumezexogaf.pdfIn PDF document text
    • http://hotelbasantresidency.com/uploads/jewekamisem.pdfIn PDF document text
    • http://duetsepolno.pl/userfiles/file/4081352981.pdfIn PDF document text
    • http://pxmonastery.org/CKEdit/upload/files/debizoloroxowosefajo.pdfIn PDF document text
    • https://nvsrolko.org/ckfinder/userfiles/files/74121298725.pdfIn PDF document text
    • https://nirkongrp.com/ckfinder/userfiles/files/daselu.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16130dbb03dbc2---21718283662.pdfIn PDF document text
    • http://kengosushionlineorder.com/uploads/files/nureraxivida.pdfIn PDF document text
    • http://m2m2design.com/userfiles/dexeriwafonerodunefenul.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/potupezakudog.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/S30rS-6n6vg/uplcv?utm_term=fast+and+furious+6+tamilyogiPDF 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_off0000dab6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAB6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f2c8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2C8 18000 bytes
SHA-256: 01a9b84efd657ac9c1c1179871eeac7242043e2dc17bcb3c2d8f77aaeb739067
font_02_sfnt_off000121e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121E2 10924 bytes
SHA-256: 5b4d6dcd0412f0a16a8f483289cc3f4a2b04f53fae9f89e450bf7ed10b8c78f6