Malicious PDF — malware analysis report

Static analysis result for SHA-256 041b58a659b892d3…

MALICIOUS

PDF

72.8 KB Created: 2021-09-18 15:07:38 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: 1843f9c973f0124c06c5f445cb1660f1 SHA-1: 71bc442e2e9956f8a96d754e5dc7062d4a9ba02e SHA-256: 041b58a659b892d320f335ca613a24f5c080173a9f5d21145f8909230c5c1d88
156 Risk Score

Malware Insights

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

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of embedded URLs and the nature of the heuristics indicate an attempt to direct users to malicious or compromised external resources, likely for phishing or further malware delivery.

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 http://abimobiliare.pl/pliki/File/gitizevufiwinovosutewax.pdf In PDF document text
    • http://asavn.vn/uploads/userfiles/files/ligegibusus.pdfIn PDF document text
    • http://colorfusion.us/admin/images/file/vamavikusot.pdfIn PDF document text
    • https://ycb.one/pro_pic/files/navugegozevuxag.pdfIn PDF document text
    • http://3asoft.vn/img/files/71358934466.pdfIn PDF document text
    • http://fantasypartyentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613597143518d---pasagotumijenifexesininaj.pdfIn PDF document text
    • https://avukatwebsitesi.kocgrafik.net/upload/files/92778963902.pdfIn PDF document text
    • http://thaimassageboy.com/ckfinder/userfiles/files/87429102337.pdfIn PDF document text
    • http://vmkmsz.hu/userfiles/file/voruri.pdfIn PDF document text
    • https://www.domaine-de-la-ferme.fr/ckfinder/userfiles/files/28483477994.pdfIn PDF document text
    • https://www.sensiblemachines.com/ckfinder/core/connector/php/files/79263657694.pdfIn PDF document text
    • http://www.cda.org.hk/ckfinder/userfiles/files/46743801617.pdfIn PDF document text
    • http://verzorgingsindex.nl/images/uploads/nojalajojebufetakeke.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/618c240c7a06e465b0a407780fda8700/pojomolakut.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/2b4ea36087f2da6c464d2faddf52bf25/87870190131.pdfIn PDF document text
    • http://hockjoohin.com/admin/uploads/file/24753563364.pdfIn PDF document text
    • http://lixupeng.com/uploads/files/tidiledapudixigumajawokov.pdfIn PDF document text
    • https://tskrea.com/userfiles/file/7297242026.pdfIn PDF document text
    • http://serdceprirody.ru/userfiles/file/73403939220.pdfIn PDF document text
    • https://portofcrotone.com/dati/upload/file/13064210483.pdfIn PDF document text
    • http://xn--nellieskche-0hb.de/userfiles/file/98322349761.pdfIn PDF document text
    • http://makeyourpartnermelt.com/userfiles/file/47997881635.pdfIn PDF document text
    • https://gangnampools.com/contents/files/77376087283.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=best+free+kjv+bible+app+for+androidPDF 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_off0000b903.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB903 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d11a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD11A 10972 bytes
SHA-256: f01570f8a3b1ca0cf26061faee44a5cb9539760187883e90004e688dec41984f
font_02_sfnt_off0000ea76.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEA76 16884 bytes
SHA-256: 873598de22d7cca82d9b36425d27bd77efb97aa6fd1c89352a13037a0af67e88