Malicious PDF — malware analysis report

Static analysis result for SHA-256 2dccf553311a4cdf…

MALICIOUS

PDF

80.8 KB Created: 2021-09-17 13:26:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: b9c3c4e516c64f6b1e09e7b59f33f6e9 SHA-1: 4cc7fdc83fbbc331064e78f522d4514bc1c5bf00 SHA-256: 2dccf553311a4cdfffcca913674b2ac7bd09200bb9b870e16926fc19d6b09399
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution through these links. No scripts were extracted, and the document body was unreadable, so the rationale is based on the URL analysis and heuristic firings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://synerhu.ru/uplcv?utm_term=minecraft+java+edition+download+for+android+phone PDF link annotation
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/b7319f7e2c768aa29ac126f0a89832ca/89457359426.pdfIn PDF document text
    • http://artgrafika.cz/userfiles/file/fepavafawomi.pdfIn PDF document text
    • http://tecsun-moscow.ru/docs/file/19921895672.pdfIn PDF document text
    • https://medosojewellery.com/userfiles/files/wixemoku.pdfIn PDF document text
    • http://gaudi.tw/upload/files/nosuxofubasox.pdfIn PDF document text
    • http://lapmaymn.samdigroup.vn/app/webroot/upload/files/85397832576.pdfIn PDF document text
    • https://cosanuesa.com/componentes/editor/ckfinder/userfiles/files/jixar.pdfIn PDF document text
    • http://akbarestate.com/survey/userfiles/files/sitavesagexixejunav.pdfIn PDF document text
    • https://garraldaarquitectura.com/garralda_userfiles/files/kewefefipofomijaririzisux.pdfIn PDF document text
    • https://bucatariizidite.ro/printuri-fi/files/nixup.pdfIn PDF document text
    • http://kd-council.com/upfile/files/82702071906.pdfIn PDF document text
    • http://app0.linkeo.it/ckfinder/userfiles/files/varet.pdfIn PDF document text
    • https://farsiherbal.com/cache/fck_files/file/kudaxakuzobevegiseluwamit.pdfIn PDF document text
    • http://parentini.it/userfiles/files/fegixefevowowefa.pdfIn PDF document text
    • https://lesartsdansmonjardin.com/userfiles/file/20210907192709.pdfIn PDF document text
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/161380879dcec7---lukokozim.pdfIn PDF document text
    • http://balashixa.inhome360.ru/admin/ckfinder/userfiles/files/tivijejijuzewixujotovad.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/34g4mjjra0liknql4q0hppeltb/96460828254.pdfIn PDF document text
    • http://restaurant-lyons.fr/userfiles/file/fewesakupoti.pdfIn PDF document text
    • https://edenestates.com/ckfinder/userfiles/files/29006791184.pdfIn PDF document text
    • https://alansglobalservices.com/ckfinder/userfiles/files/40127193155.pdfIn PDF document text
    • http://byecook.com/ckupload/files/potepuxoxunorekesuzejowen.pdfIn PDF document text
    • 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_off0000d9c2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9C2 16664 bytes
SHA-256: ed55cec26e5f2fb1d8fb7bf79231f2149a25d1ba781466b3bdd9b79697a1aa6d
font_01_sfnt_off000104cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104CB 10824 bytes
SHA-256: 165f2759ffcd266a09a6d5620dcb48648c7467b4bd9936ec760e12225d0c4094
font_02_sfnt_off00011db4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DB4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1