Malicious PDF — malware analysis report

Static analysis result for SHA-256 6277398b1c6f6a46…

MALICIOUS

PDF

93.1 KB Created: 2021-07-07 18:13:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: f082d5bb2b0c3a733984bb48cd24e333 SHA-1: 904edbd7170b114e1e16fe959cddd7b06d859cc8 SHA-256: 6277398b1c6f6a46fff2428630508ea518496153babde7dbe009bfde879dc2e6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 User Execution: Malicious Link

The PDF contains numerous links, many pointing to compromised WordPress sites, indicating a link farm designed to lure users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL heuristics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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 http://vudafrique.com/wp-content/plugins/super-forms/uploads/php/files/cdcb158a1da2478a0eac695ec82e1447/9847778095.pdf In PDF document text
    • https://him-home.ru/wp-content/plugins/super-forms/uploads/php/files/bc10d06b5cbeac1e24855ac7e6796163/wezukaxinuvojaniv.pdfIn PDF document text
    • https://nikken-engineer.jp/export/sd205/www/jp/r/e/gmoserver/8/6/sd0748886/nikken-engineer.jp/fckeditor/upload/file/98909747603.pdfIn PDF document text
    • https://djhelaly.com/wp-content/plugins/super-forms/uploads/php/files/5fec23f0dcbc9c3f0ccdd19aeecc1b1c/68342143488.pdfIn PDF document text
    • http://vo23.ru/upload/file/gabikezagijora.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cfe343d425e---nufezorowogujepofawe.pdfIn PDF document text
    • http://tfh-filter.hu/_user/file/36235600779.pdfIn PDF document text
    • http://akinmedical.com/uploads/file/mikotavofusevodawelanuwix.pdfIn PDF document text
    • http://kurskodkb.ru/page_edit/_samples/userfiles/files/piruko.pdfIn PDF document text
    • http://bahattinburyan.com/userfiles/file/worimijebaredolokate.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/f7bda4c2eaebfec1a88c7bb5ce0530a6/60293105678.pdfIn PDF document text
    • http://bsbcarpet.com/userfiles/file/nogavez.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c238e122cd1---40422032244.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1608fe41b683d6---kizori.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b86189bd985---4229554219.pdfIn PDF document text
    • http://cuacongtrinh.vn/upload/files/68059706729.pdfIn PDF document text
    • http://nineslash.com/user_file/file/rijidel.pdfIn PDF document text
    • https://afriqueitnews.com/wp-content/plugins/super-forms/uploads/php/files/8cb7a4e7d9141de3dbc4f994c65a95e4/jogebuke.pdfIn PDF document text
    • https://robotics-institute.com/wp-content/plugins/super-forms/uploads/php/files/moalmrnopmn0p6oigls2p3bukh/69557381040.pdfIn PDF document text
    • http://border-inn.com/CKEdit/upload/files/30644731420.pdfIn PDF document text
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/3gq3s0v01e4mokefqbr1pvl224/48358308474.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/6bdec23d4fe4514e4d9c5b4c03310f01/57105603131.pdfIn PDF document text
    • http://www.absolutecateringla.com/wp-content/plugins/formcraft/file-upload/server/content/files/160824c2acd0fb---xiromanolojomaralu.pdfIn PDF document text
    • http://www.mediacomriccione.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607f43cb3396a---zigijuwenabulopizanet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+get+free+cars+in+gta+5+onlinePDF 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_off0001092e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1092E 10720 bytes
SHA-256: 58f451a397f38e0dfc2821f939247d8e1b92b7ae10d30d278845b84a3c8cc017
font_01_sfnt_off00012202.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12202 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013a14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13A14 17116 bytes
SHA-256: 8e1f30592d1c5cc8e2634509046872f2fd3fceb793c9000ebd4be60b258fdf4c