Malicious PDF — malware analysis report

Static analysis result for SHA-256 21064fd115fc4d8c…

MALICIOUS

PDF

84.3 KB Created: 2021-09-04 21:02:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 218d4ae794f52edba20dc4fb6d44ee9d SHA-1: cd7f573e109ef349d2301d8796a3a25ccf4b87ca SHA-256: 21064fd115fc4d8c685cba502af4a94129e28cec671c92729c6d85646dd4cfb9
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 functions as a link farm, with numerous URLs pointing to compromised websites and disposable domains, suggesting an attempt to lure users to malicious content. The PDF structure and embedded links are consistent with phishing campaigns designed to distribute malware or steal credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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://infrapanel-alegjobbfutes.hu/userfiles/file/zedukemuvatijegofese.pdf In PDF document text
    • https://wwa.bdbabymart.com/app/webroot/ckfinder/userfiles/files/vojawofux.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/45048099639.pdfIn PDF document text
    • https://makemycake.gr/wp-content/plugins/super-forms/uploads/php/files/8gq28ih0at4ei2gn72n025gpgo/25640320815.pdfIn PDF document text
    • https://binarbaidservices.com/public_html/userfiles/file/pisedinoneru.pdfIn PDF document text
    • http://www.ecvbrass.ch/user/web/file/6453177915.pdfIn PDF document text
    • https://lllk.ru/wp-content/plugins/super-forms/uploads/php/files/f24e5b4d74bca484c1ea175736b3c75d/2352445842.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084071e1c5cb---95005809102.pdfIn PDF document text
    • https://ajwatravel.com/wheelmarine/userfiles/file/8958313367.pdfIn PDF document text
    • https://baoholaodong24.com/userfiles/file/rifomimem.pdfIn PDF document text
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607b0569c9d7b---gurebonudujaxunikatapar.pdfIn PDF document text
    • http://househouse.it/userfiles/files/bobasubu.pdfIn PDF document text
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a5361a4f048---turosekoperevenepifurifuf.pdfIn PDF document text
    • http://grotech.in/userfiles/file/zenisipazumiwodosufo.pdfIn PDF document text
    • https://www.truesdalepainting.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7625e3fe36---sinusogupawozewavat.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0267ceb3ae---21247311469.pdfIn PDF document text
    • http://unewstoday.com/task/userimages/file/37026732948.pdfIn PDF document text
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/160747b3929f4e---6780757695.pdfIn PDF document text
    • http://elmiraclassiccountry.com/wp-content/plugins/super-forms/uploads/php/files/fgdv3ur3375nvm69ts68ulab44/42329307051.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=linak+la36+user+manualPDF 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_off0000e4f4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE4F4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fd06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD06 18040 bytes
SHA-256: a3c51bad82656a9fc6ce1921288276080c03ec493160be39b3f1b5e5c9c2dc60
font_02_sfnt_off00012c22.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C22 10540 bytes
SHA-256: b44473fb7c3c3eddd0c30670901a53489645e72a61fef831397dc578a36ab853