Malicious PDF — malware analysis report

Static analysis result for SHA-256 8c879cdc12185460…

MALICIOUS

PDF

80.5 KB Created: 2021-09-17 20:50:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 223938ed019b7da2c58ac0e6b06fae5d SHA-1: a10105f3b10f7d510e891cb196c4af483f1f407f SHA-256: 8c879cdc121854608e3ef3252654b79d13105e96812546b48e2cf6933d537c07
156 Risk Score

Malware Insights

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

The PDF contains a link farm, directing users to multiple external URLs, some of which are hosted on compromised CMS platforms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of numerous links and the nature of some hosting suggest an attempt to obscure the true destination or leverage compromised infrastructure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://istruttorecinofilo.it/userfiles/file/87046170343.pdf In PDF document text
    • http://7166867.ru/ckfinder/userfiles/files/88949783999.pdfIn PDF document text
    • https://ibericadearmerias.com/file/didaluj.pdfIn PDF document text
    • https://limpjet.com.br/wp-content/plugins/super-forms/uploads/php/files/7cf77539a10a331dff5aab25e5f3c102/86955707200.pdfIn PDF document text
    • http://hemeringen.de/ckeditor_ablage/userfiles/files/fixajufufobi.pdfIn PDF document text
    • http://transcash.com/ci/userfiles/files/luriviwowe.pdfIn PDF document text
    • https://glass-haus.ru/wp-content/plugins/super-forms/uploads/php/files/e0292dbd940b867f50fed7e5589d9caa/51072004153.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/wuwawemoxibekatejev.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16132bdd93cc34---fulozetelirapiwulone.pdfIn PDF document text
    • https://piauiaqui.com/ckfinder/files/zonovodo.pdfIn PDF document text
    • https://atx-stroy.ru/wp-content/plugins/super-forms/uploads/php/files/145d5175651046982edc78c16256d011/67256154125.pdfIn PDF document text
    • http://malopolskiszlakwinny.pl/upload/File/bujujowi.pdfIn PDF document text
    • http://www.uc-kushiro.net/images/library/File/97493361595.pdfIn PDF document text
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161371ad60dc6b---kinamapilegijidesibus.pdfIn PDF document text
    • https://energiadirect.pl/application/resources/ckfinder/userfiles/files/rativivexurizira.pdfIn PDF document text
    • https://baigiangtoanhoc.com/upload/files/gefuwapipejibukotow.pdfIn PDF document text
    • http://24hnbc.com/assets/ckfinder/core/connector/php/uploads/files/diruzifatamixik.pdfIn PDF document text
    • https://mondoaudio.it/img/uploaded/file/6020408567.pdfIn PDF document text
    • http://quatanggiabao.com/images/uploads/files/6866393453.pdfIn PDF document text
    • http://www.srijonihealinghome.com/fckimages/file/23888015707.pdfIn PDF document text
    • http://smwiarus.pl/ckfinder/userfiles/files/68871730494.pdfIn PDF document text
    • https://forumhrdbekasi.com/webroot/userfiles/files/nesirebuwemelawidotibix.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=gta+phone+game+downloadPDF link annotation
    • http://forum-auto.ru/data/files/ritinufasi.pdfIn 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://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_off0000d4a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4A7 18752 bytes
SHA-256: be0edb3221dcbfa42fb59aabd113e7e381e8ee307eb49d6f6c3f110eda973534
font_01_sfnt_off00010501.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10501 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011d18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11D18 10604 bytes
SHA-256: 157837265379f94c0ebae50fa232a3cd67558610a0e7990aeb03ee046a979122