Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4afbc0b08804366…

MALICIOUS

PDF

72.2 KB Created: 2021-06-09 04:52:32 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-11-23
MD5: ecf8301fe730c41e299f8501b83add10 SHA-1: 3a36bcab4e5b0711609db91c199db85db4e104f9 SHA-256: a4afbc0b088043664b28a7459b053303eecdca5a880cdd2f4992bfdc41758623
156 Risk Score

Malware Insights

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

The PDF contains a link farm that directs users to various websites, some of which appear to be compromised CMS uploads, under the guise of offering free ebooks. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. While no scripts were directly extracted, the PDF structure and embedded URLs suggest it's designed to redirect users to malicious content.

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://garglob.ru/uplcv?utm_term=free+nancy+drew+ebooks PDF link annotation
    • https://mymovingestimate.com/wp-content/plugins/super-forms/uploads/php/files/ed566a4b6dc425a04068d43adafb5870/xenomiwilinigegaxovovaga.pdfIn PDF document text
    • http://www.reroofingbrisbaneqld.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16093b616e3c33---57467580900.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160baa761b91b1---90579976526.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/8b30943b630153754e29ea9b2890d715/nisalewojowupofur.pdfIn PDF document text
    • http://agiusfuneraldirectors.com/files/file/53511633364.pdfIn PDF document text
    • http://aptchasers.com/FCKeditor/userfiles/file/gomanupujurane.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1606e765b9078f---19479878519.pdfIn PDF document text
    • https://www.spoton.pet/wp-content/plugins/super-forms/uploads/php/files/62oa0449hui9ddghrhgsepj71a/lulutijatojuli.pdfIn PDF document text
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077ba9eb5fe9---87172651272.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aa247eec01---baseruro.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607f98ba471df---dovurikiwawovama.pdfIn PDF document text
    • http://ahdongjiu.com/upload_fck/file/2021-4-29/20210429195432763764.pdfIn PDF document text
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609dd60be0dea---nufaj.pdfIn PDF document text
    • http://alemotta.com/resources/original/file/suzilapekidojizatoxe.pdfIn PDF document text
    • https://abofahed.com/userfiles/file/ravegujixipenoworawedane.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/2cee247d761197a0852e64502a8a1f38/jiwulobodolo.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/p4pkaucscnbbj3eui1745ov8v6/78627936063.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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_off0000da86.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDA86 5252 bytes
SHA-256: 7e1cf4f8943dcc7c589bc72d5fa8c5a1d59a9069746b046c06e0f13b74e65832
font_01_sfnt_off0000ec8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC8D 11384 bytes
SHA-256: af63355fb6832c349af5f46dfd6182c31f786b94f32521095a1a1f937737adfd