Malicious PDF — malware analysis report

Static analysis result for SHA-256 604cccac1a9a07a4…

MALICIOUS

PDF

83.8 KB Created: 2021-09-23 09:05:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 712428c9a293763e902f41da32990f71 SHA-1: 29b657077457b873c668e40c671993ba5ff3b0b4 SHA-256: 604cccac1a9a07a449ecc24fa047037011ab032bd4f6bf63c78c9b9dd28ae36d
146 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of numerous external URIs, including a link farm on disposable hosting, suggests a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the PDF structure and embedded URLs point towards an attempt to redirect users to malicious sites, likely as part of a spearphishing campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9945

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
  • 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.
  • QR-code redirect lure medium SE_QR_LURE
    Document instructs the user to scan a QR code with a phone — consistent with QR phishing, but also common in legitimate documents
  • 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://crysiq.ru/uplcv?utm_term=korean+grammar+in+use+beginner+pdf PDF link annotation
    • http://denkobarbell.com/_upload/files/75616170946.pdfIn PDF document text
    • http://gartenbaukoeln.de/uploads/files/30870560514.pdfIn PDF document text
    • http://vertex-decor.com/userfiles/file/88935133896.pdfIn PDF document text
    • https://7foro.exceltur.org/exceltur_nuevo/ckfinder/userfiles/files/77448246954.pdfIn PDF document text
    • http://frutapac.es/ckfinder/userfiles/files/jojawepaw.pdfIn PDF document text
    • http://fobosgrunt.ru/files/ckfinder/files/23107073408.pdfIn PDF document text
    • http://ephtour.com/FileData/ckfinder/files/20210914_E27F2B196DE4FB89.pdfIn PDF document text
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140655c75a20---76148461289.pdfIn PDF document text
    • http://zkmeiqi.com/admin/ckfinder/upfile/files/31446204348.pdfIn PDF document text
    • http://www.cda.org.hk/ckfinder/userfiles/files/navepoxu.pdfIn PDF document text
    • http://apmnir.ro/fckfiles/file/rirexegowuxigixu.pdfIn PDF document text
    • https://hinodanang.com/uploads/image/files/39013053924.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/ed4214d7c0eac9086644bb3719d1265d/labuj.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/xukapomiworewufilajekusid.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/91401578219.pdfIn PDF document text
    • http://fotostudiovaccari.it/userfiles/files/gotijunuvuxab.pdfIn PDF document text
    • http://joyearland.com/ckfinder/userfiles/files/sinawafako.pdfIn PDF document text
    • http://generoussecurity.com/uploads/rilunigejunoworosafaw.pdfIn PDF document text
    • http://viethanit.vn/hinhanh/file/76976031592.pdfIn PDF document text
    • https://rajaunited.com/contents/files/wusobaxidibalif.pdfIn PDF document text
    • http://grafichesirio.com/userfiles/files/kikoxisubopebonabajisil.pdfIn PDF document text
    • https://kapefashion.com/files/files/ravewogoziniwerufub.pdfIn PDF document text
    • https://immo-macedo.lu/userfiles/files/ruxemede.pdfIn PDF document text
    • http://rsport.eu/yonexshop/static/file/sazorowojotuweveximinowax.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_off0000d9d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9D0 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f1e7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF1E7 10928 bytes
SHA-256: 93c3545ad2c45925039a6d92ef9463949004960c039880d7ccf8fc5635dcff57
font_02_sfnt_off00010abb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10ABB 21272 bytes
SHA-256: c2ae739521bebacb691e19d7fe383c2fdaad8ba9dff6e22e6fcbe94300b66ac0