Malicious PDF — malware analysis report

Static analysis result for SHA-256 7271edc584f27821…

MALICIOUS

PDF

84.1 KB Created: 2021-09-19 11:15:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 4efc9866edd43c78359e85e107e0d29b SHA-1: 5e177d341fa148b49642d75d17985e031b2c8ded SHA-256: 7271edc584f2782196f7ce7e7b008148f3aa9e05ba3bc2a52dbe98f34bcb8815
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users. The primary purpose appears to be directing users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://nutstudio.it/userfiles/file/pevivarufedo.pdf In PDF document text
    • http://delta-serwis.pl/pliki/15293138760.pdfIn PDF document text
    • https://kottayammedicalcollege.org/CMS/ckfinder/userfiles/files/tajitusuwoso.pdfIn PDF document text
    • http://www.oiseaubleu-promo.fr/userfiles/file/nazejidixezo.pdfIn PDF document text
    • http://giasuminhtam.com/Images_upload/files/96841874730.pdfIn PDF document text
    • http://tl-maskinfabrik.dk/userfiles/file/xosowuvaz.pdfIn PDF document text
    • https://milosislandrooms.gr/userfiles/file/jomigi.pdfIn PDF document text
    • http://cuuhoatudong.com/upload/files/6974052298.pdfIn PDF document text
    • http://www.norestim.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16141fc966b934---54764865431.pdfIn PDF document text
    • http://top1np.com/ckfinder/userfiles/files/lifubaxowafisap.pdfIn PDF document text
    • http://civicwomen.com/ckfiles/files/58972646748.pdfIn PDF document text
    • http://gelateriacool.it/userfiles/files/8047158322.pdfIn PDF document text
    • http://dogomanhnghia.com/uploads/files/2548587045.pdfIn PDF document text
    • https://gencatakan.com/upload/file/roraxep.pdfIn PDF document text
    • http://prestopc.it/upload/file/87050209447.pdfIn PDF document text
    • http://tksvolga.ru/userfiles/file/89388275354.pdfIn PDF document text
    • https://betonwerkendejonge.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16143de199155f---pagepedasaladovuboj.pdfIn PDF document text
    • https://autoprofi.ua/userfiles/file/pelepe.pdfIn PDF document text
    • http://altinay-law.com/images/file/44028148254.pdfIn PDF document text
    • https://thesmithgrouphouston.com/wp-content/plugins/super-forms/uploads/php/files/0f9ff554e35b5b58c09e84a12de899ed/zowur.pdfIn PDF document text
    • https://www.hagensmarketing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16133cf7c5bc8f---35544932744.pdfIn PDF document text
    • https://ilonew.tasksplan.com/userfiles/files/newenawagafowukanil.pdfIn PDF document text
    • http://kuwaited.com/cote_dor_import/admin/ckfinder/userfiles/files/28553127941.pdfIn PDF document text
    • http://myflora888.com/ck_files/files/32529842753.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=airbrush+app+for+androidPDF 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_off0000e5c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE5C7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000fdd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD9 17484 bytes
SHA-256: 8e0aa0cec85a946ed830046e8783a31fa0ce242a910c861a60cd2bc3a9c0180a
font_02_sfnt_off00012b30.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B30 10540 bytes
SHA-256: 1edcb92e5d8f86da9a1f7b8dc6d6d8cc43278be33cbbe5808c2664df18b64e51