Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b1c6becc8d080db…

MALICIOUS

PDF

76.8 KB Created: 2021-10-04 14:51:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 31acd108bad927238d81fa6fe6282de3 SHA-1: 0af76c647786c9b21d6742618e9d82a91f1e734a SHA-256: 6b1c6becc8d080db3e3e3dc2ead51e6ba9a71092e0474a59df8886abffe660ae
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, specifically as a phishing trojan. It contains numerous links, many pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to redirect users to malicious content. While no scripts were explicitly extracted, the PDF structure and heuristic firings indicate an attempt to exploit users via external URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/161557f3846a20---97437824036.pdf In PDF document text
    • http://qkmedica.com/uploads/userfiles/file/40016219694.pdfIn PDF document text
    • http://qapoll.com/2015/vat/upload/files/rilite.pdfIn PDF document text
    • https://oncallanatomist.org/ckfinder/userfiles/files/bijafimotapanerifojem.pdfIn PDF document text
    • http://workcoop.org/fckeditor/userimages/file/20210913010749.pdfIn PDF document text
    • http://steelfurniturecn.com/d/files/gilobizogebebix.pdfIn PDF document text
    • https://too.kg/wp-content/plugins/super-forms/uploads/php/files/548d7ddd6a001a2237c34cfb08139cab/rakakazomaxitipepowub.pdfIn PDF document text
    • http://ensky-chemical.com/upload/files/jijojoto.pdfIn PDF document text
    • http://cgpreceptor.com/ckfinder/userfiles/files/povunopilakifoguku.pdfIn PDF document text
    • http://lahma.pl/_u/userfiles/file/sojukozo.pdfIn PDF document text
    • http://brmxn.com/userfiles/file/20210907120235_vfugjd.pdfIn PDF document text
    • https://ratco-hardware.com/Ups/files/21271275373.pdfIn PDF document text
    • https://freshchannels.com/home/sites/freshchannels/public_html/ckfinder/userfiles/files/16787552789.pdfIn PDF document text
    • http://www.radioemka.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135529d211c6---pafebis.pdfIn PDF document text
    • http://customize.fr/fckeditor/editor/filemanager/connectors/php/img/Editor/file/bozulika.pdfIn PDF document text
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1615090b1c18be---33069691969.pdfIn PDF document text
    • https://maths-pdf.fr/ckfinder/userfiles/files/7742293525.pdfIn PDF document text
    • https://viajespereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614411bae362f---56311684345.pdfIn PDF document text
    • http://lifecontinues.ru/images/files/genazawer.pdfIn PDF document text
    • http://e-menu.hu/editor_up/wuwagadotomakopagovukuw.pdfIn PDF document text
    • http://ammk.sk/userfiles/file/wisub.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161519598eb367---52770260727.pdfIn PDF document text
    • https://megacook.pt/site/upload/file/35841704445.pdfIn PDF document text
    • http://laxycoffee.com/upload/files/sivek.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=perspectives+in+nutrition+pdfPDF 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_off0000c7ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC7ED 10572 bytes
SHA-256: ebfa276dbfb396975ab433e98402274d1a123d44cd1ca7c82c9e1c072bdc0b89
font_01_sfnt_off0000e039.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE039 17536 bytes
SHA-256: 9b61434101aed190ded46ad99f534af28c627b513de8b5d1b4f9487c0eec773e
font_02_sfnt_off00010d32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10D32 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1