Malicious PDF — malware analysis report

Static analysis result for SHA-256 d26870796039fb54…

MALICIOUS

PDF

77.2 KB Created: 2021-09-13 19:46:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: f10f77e916fe5d0b4c817652d03054f1 SHA-1: 252f1ae2824eb067963bed528766dfbd579bd65e SHA-256: d26870796039fb5488e253a44147ffc3cdf9e939bf6136fbc5ace45c1d895079
156 Risk Score

Malware Insights

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

This PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous links, many pointing to domains associated with compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, providing no direct user-facing content but containing embedded URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://pomacanthe-art.fr/imagebeforeafter/files/28236197422.pdf In PDF document text
    • http://knuhpharm.kr/userfiles/file/20210912035554.pdfIn PDF document text
    • http://linhkienhunganh.vn/luutru/files/muriwomazapomoxixunaxo.pdfIn PDF document text
    • https://vegas-shop.net/uploads/files/tagejilukigugasefeposisek.pdfIn PDF document text
    • http://muacuoi.vn/Pictures/files/liwalogojikejexirilu.pdfIn PDF document text
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16138df8842739---60733576245.pdfIn PDF document text
    • https://szekszardportal.hu/userfiles/file/55636046282.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16134feac11736---78701304537.pdfIn PDF document text
    • https://voziky-paletove.cz/mctree.cz/pictures/other/files/71125886583.pdfIn PDF document text
    • http://habitat3.eu/userfiles/files/sovoliwegepuded.pdfIn PDF document text
    • http://ahkkpcm.org/userfiles/24594958651.pdfIn PDF document text
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/1613f4f399cd3b---36481791597.pdfIn PDF document text
    • https://ibliberia.com/ckfinder/userfiles/files/77661986674.pdfIn PDF document text
    • https://wwa.bdbabymart.com/app/webroot/ckfinder/userfiles/files/15544312002.pdfIn PDF document text
    • https://vhssirimpanam.org/ckfinder/userfiles/files/31771521239.pdfIn PDF document text
    • https://vietnamwelder.vn/uploads/news_file/memuveroxazufigu.pdfIn PDF document text
    • https://pomtco.com/technical/files/file/33177798914.pdfIn PDF document text
    • http://www.verneteco.com/ckfinder/userfiles/files/1119336304.pdfIn PDF document text
    • http://gancza.pl/userfiles/file/95327699320.pdfIn PDF document text
    • https://leo.tw/upload/ckeditor/files/bofoko.pdfIn PDF document text
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/bff9jlfl8lbvb11ev4vdh4082k/boditutenanepin.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+play+wma+on+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_off0000ca0f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA0F 17476 bytes
SHA-256: dde1f7bb3a8d2c170608338a9a4f2054f9bfbcc8e4d40fe40ee4b3a34b768d6c
font_01_sfnt_off0000f7a2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7A2 10444 bytes
SHA-256: 5c72238472055883460941969f6f7c092a955221369a4dda1f6e52beec15700b
font_02_sfnt_off00010f40.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F40 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1