Malicious PDF — malware analysis report

Static analysis result for SHA-256 57bd2791a118426e…

MALICIOUS

PDF

74.9 KB Created: 2021-05-24 21:57:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-21
MD5: 0b5b999377b547e5d178af245473f6cc SHA-1: b89861dda211c6c8867a627781bb6cbc7ff0bd94 SHA-256: 57bd2791a118426e1414134b3715cbe21328767a03e651eee4529b42fe96cd4b
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to phish or distribute further malware. Although no scripts were directly extracted, the PDF structure and embedded links are indicative of a malicious document, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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
  • 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://doellefjelde-mussemarked.dk/images/newsmail/file/66036123401.pdf In PDF document text
    • http://jnnycc.org/userfiles/file/kunipemubo.pdfIn PDF document text
    • https://www.basur-tedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ba1ec497c5---jumezuruma.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607714f2109a7---wowakuwafenoved.pdfIn PDF document text
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/ensqrj7t2djeg0arj8qcd9taqu/56041711486.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607e0d9f0c793---dowetabo.pdfIn PDF document text
    • https://stopserv.ru/files/file/83019887390.pdfIn PDF document text
    • http://adams-gold.ru/archive/image/file/28949869064.pdfIn PDF document text
    • http://www.etoiles-recrutement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ce0e47af59---xoxabulusotod.pdfIn PDF document text
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/3e025d9c3fefe18211c2c028cb70fa82/daxukulogu.pdfIn PDF document text
    • http://technoculture.cz/admin/upload/file/lunanotevodenozetabup.pdfIn PDF document text
    • https://mollis.rs//files/divulejivadokifezup.pdfIn PDF document text
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/aad1a44b1c01964c8167a330607770ea/83166030801.pdfIn PDF document text
    • https://bluebeakbranding.com/wp-content/plugins/super-forms/uploads/php/files/0368b969eb8306ddb5525cdb2c6801d9/6771340797.pdfIn PDF document text
    • https://eyestech.in/wp-content/plugins/super-forms/uploads/php/files/sgmh5hh03uons970l38scdk4pt/gopuvizuzazufowofexoxuz.pdfIn PDF document text
    • http://wisdomtours.net/upload/file/supajonesoraxagujezama.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160aa7fae16125---xesotumu.pdfIn PDF document text
    • http://analogsys.com/uploaded/file/49161590260900069ef444.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=how+to+make+friendship+bracelets+easy+at+homePDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e674.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE674 5756 bytes
SHA-256: f2ff0c13f46d1163d61beb4e5d76ede59d672f7b31bc896d7d61df80ddb519be
font_01_sfnt_off0000f9f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F5 10668 bytes
SHA-256: 315cc6302bbcdb693b38f6983b699ceb967725cdb7ec2c64fd6550c06b2170be