Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e4c13083f32a9e0…

MALICIOUS

PDF

82.0 KB Created: 2021-09-20 03:37:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 6594056bcc6d095faaf416373ddd4fda SHA-1: 7864be80941a4ac4e95f3f6f34aab1c0a15ee4c7 SHA-256: 8e4c13083f32a9e08ee87b4dec55bee369b0af6c15a0a176417bb9f1f74a0e94
156 Risk Score

Malware Insights

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

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting. The primary attack pattern involves luring users to these external sites, likely for credential harvesting or further malware delivery.

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 http://studiobonvino.com/userfiles/files/65451929643.pdf In PDF document text
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/4eaa1c99087ef7d1ffd5ac6cfda80974/zetuxafomavoxosipeduke.pdfIn PDF document text
    • http://ijdssymposium.eu/upload/nivojuzovigofe.pdfIn PDF document text
    • https://vozilasavozacem.rs/files/2984108910.pdfIn PDF document text
    • http://foire-fromages-et-vins.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613cd79ec4512---lebowajusudorawudot.pdfIn PDF document text
    • https://yidinfo.net/wp-content/plugins/super-forms/uploads/php/files/9fk6eci29olm2f0eocatrn7fp4/sufijegonosogota.pdfIn PDF document text
    • https://vmwarts.com/ecovic/file/34484756721.pdfIn PDF document text
    • http://serramentisiciliano.it/userfiles/files/zapamiwobogome.pdfIn PDF document text
    • http://www.trisad.kz/ckfinder/userfiles/files/rudajoz.pdfIn PDF document text
    • http://knx-shop.ru/admin/ckfinder/userfiles/files/67130246829.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/punutipomi.pdfIn PDF document text
    • http://logicparcel.net/uploadsEditorfile/74988185567.pdfIn PDF document text
    • http://handbook.hu/upload/page/file/xutonijoxikiforiwuxikedot.pdfIn PDF document text
    • https://fo-prefectures.com/pages/files/79490031059.pdfIn PDF document text
    • http://st-ark.it/userfiles/files/67043380705.pdfIn PDF document text
    • https://prospr.fr/ckfinder/userfiles/files/83240650055.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139913faa9ea---36722746787.pdfIn PDF document text
    • http://samurairamenbar.com/uploads/files/tezajokezaxoregutunerinil.pdfIn PDF document text
    • http://china-miyaco.com/img/file/20219213525.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16130b128f1c32---wepilapimi.pdfIn PDF document text
    • http://bkht.vn/userfiles/file/dasute.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=strumming+pattern+for+count+on+mePDF 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_off0000dba4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDBA4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f3b6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF3B6 17804 bytes
SHA-256: f12301386a9543ceb44c649ae1c5a9ab5f750ced35f65ad1b1367d17b742f795
font_02_sfnt_off00012196.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12196 10784 bytes
SHA-256: db4d638cbbd22f41641dfda4c02b7a0ea58f6a397afcaed4f67b042d7f28e600