Malicious PDF — malware analysis report

Static analysis result for SHA-256 fe81dadfc1065eea…

MALICIOUS

PDF

81.9 KB Created: 2021-09-20 19:47:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: ebef60b4f702f5cc08c27619ee89e02a SHA-1: 39b2d6ef740a75b5864366de6c1ee35a98b31526 SHA-256: fe81dadfc1065eea1d58d9b9af3f594afdfd64ebb9cf7b96e73080a66098eeef
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to disposable hosting or compromised CMS upload directories, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://bd-sokolovska.eu/userfiles/file/38934788653.pdf In PDF document text
    • http://xn--9p4b29dncp2cc6y.net/upload/fckeditor/file/70294880329.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613902636d9bb---48080574011.pdfIn PDF document text
    • https://sevenhillsgroup.net/ckfinder/userfiles/files/fojagepekudatunazoserofiw.pdfIn PDF document text
    • http://www.astmalek.cz/obrazky/file/78881730286.pdfIn PDF document text
    • http://ttccid.com/userfiles/files/31333267455.pdfIn PDF document text
    • http://le-lemniscus-incandescent.fr/ckeditor/upload/files/mefobulumirifeki.pdfIn PDF document text
    • http://csc0516.com/userfiles/file/20210905170838_7f3fw9.pdfIn PDF document text
    • https://lanjutpt1.com/contents/files/mimomenarovowivu.pdfIn PDF document text
    • http://amirmazandaranihospital.com/ckeditor/files/files/kokekalexumatuweruvuvuf.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136c184a9ba6---87490234257.pdfIn PDF document text
    • https://siliconautomation.com/userfiles/file/menuwibeguwi.pdfIn PDF document text
    • http://sxnqx.org/upload/file/Fl202109151920413588.pdfIn PDF document text
    • http://caratow.eu/userfiles/file/diwomimovorop.pdfIn PDF document text
    • https://markzone.az/wp-content/plugins/super-forms/uploads/php/files/npllta3k5bfrg1vm8o6fscr95k/bupomatebidagev.pdfIn PDF document text
    • https://tomaszbizon.tomaszbizon.pl/web/uploads/files/dobubuxonaxokelogusesefe.pdfIn PDF document text
    • http://nomayaku.com/userfiles/file/49436839057.pdfIn PDF document text
    • http://srs-budapest.hu/uploads/files/7020819867.pdfIn PDF document text
    • http://accessibilite-salle-eau.com/ckfinder/userfiles/files/gupolonewizugopirejo.pdfIn PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613b864979862---37151482042.pdfIn PDF document text
    • http://hejia-ele.net/upload/pakoma.pdfIn PDF document text
    • https://pasarant0g3l-turbo-h1t.com/contents/files/63953312031.pdfIn PDF document text
    • http://masterkontroll.hu/ckfinder/userfiles/files/6363687887.pdfIn PDF document text
    • https://www.lokalesichtbarkeit.de/wp-content/plugins/super-forms/uploads/php/files/0lvvuv38ofu015h8paqbciiapi/tomesukeranoxirekoxan.pdfIn PDF document text
    • http://newgrids.com/userfiles/file/lisenexeriluderujub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=mi+a3+problem+after+updatePDF 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_off0000d925.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD925 10792 bytes
SHA-256: ac5f48c76e1bf45740893a4b84596e846904ba507d2c942982a322efdad71136
font_01_sfnt_off0000f1cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1CC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000109de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x109DE 18556 bytes
SHA-256: 878eba7ed5eb49a334d602ca4b31d4e9c6a51ca675e754f4346e0702f7e29c2c