Malicious PDF — malware analysis report

Static analysis result for SHA-256 9ebbe3a5e1038189…

MALICIOUS

PDF

115.2 KB Created: 2021-07-03 11:26:19 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 28dce555ab793828142d78fd4ebd50ed SHA-1: bf97ba8c872e3e52b7720a75453ca6ff2238fc54 SHA-256: 9ebbe3a5e1038189dd0cae3173a2c38ebf7d881abad5f31b5e920837135542ec
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, and exhibits characteristics of a link farm pointing to compromised WordPress upload storage. Multiple heuristics indicate the PDF is designed to host numerous links, likely to facilitate phishing or malware distribution. The presence of embedded URLs and the nature of the heuristics suggest an attempt to redirect users to external, potentially malicious, sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607cd93a4397d---52589529316.pdf In PDF document text
    • http://suachuabaoduongmaynenkhi.com/img_quanganh/files/gaxokafekurajivirotaji.pdfIn PDF document text
    • http://bhhangkhong.com/upload/images/files/zozuzivigafeluraxilepez.pdfIn PDF document text
    • https://polinagerz.ru/wp-content/plugins/super-forms/uploads/php/files/cv4b5spmv9eorj5n9ipcd4d9lk/tigeb.pdfIn PDF document text
    • http://caribsplash.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607a186b0abc0---renubimexa.pdfIn PDF document text
    • http://france-ex.com/images/blog//file/34719630720.pdfIn PDF document text
    • http://firegallery.ru/img/upload/1369107995.pdfIn PDF document text
    • http://kirks-pool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef6b30eb14---duxixutozetegonidonen.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c342005aea7---rapitiba.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1607852f8f4044---kamiti.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d0380f194a8---76047453791.pdfIn PDF document text
    • https://baongochoa.com/upload/file/zuxodefezezelew.pdfIn PDF document text
    • http://lempreintedubois.fr/userfiles/lempreintedubois.fr/file/23243104845.pdfIn PDF document text
    • http://currycornersugarland.com/admin/images/file/231170090.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/a7355f0a5e9845268f4048d0f7d6f581/rivexiginagozawekugov.pdfIn PDF document text
    • https://rasathantrananotech.com/ckfinder/userfiles/files/nijutukebafariranufufetol.pdfIn PDF document text
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/1607f88b582f5c---86297875778.pdfIn PDF document text
    • https://web-sila.ru/wp-content/plugins/super-forms/uploads/php/files/91d06d8ea73200850caac7341032704f/safaburadasafaj.pdfIn PDF document text
    • http://benhvienlaptop.biz/userfiles/file/72454068408.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609ce0fbb1dc1---pawamum.pdfIn PDF document text
    • https://visaonline-vn.com/wp-content/plugins/super-forms/uploads/php/files/0ar2kk6fat4enp267ue2hni667/78752421967.pdfIn PDF document text
    • https://pensiunea-escape.ro/ckfinder/userfiles/files/15986605839.pdfIn PDF document text
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/349cb6e675e5705d05a3660347f8b7df/nofafodotamolaluti.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/cv9VXjIrmdE/uplcv?utm_term=fractional+distillation+of+petroleum+in+a+fractionating+column+is+carried+out+in+aPDF 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_off00015e92.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15E92 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000176a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x176A4 17848 bytes
SHA-256: 6d4057895a9ca119183ad257992f102ec5e6deefe114b103807cbb2626d72f7e
font_02_sfnt_off0001a570.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A570 11040 bytes
SHA-256: 71039e781374ce6e45461eab4eaf447f88a53795a010bb4bb9603370301003a7