Malicious PDF — malware analysis report

Static analysis result for SHA-256 55b572cfc7227b42…

MALICIOUS

PDF

87.7 KB Created: 2021-10-10 19:04:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 30b76da9928cf35eb8431405a7fab23e SHA-1: c59f4201f79dfe600643a59c7676f78b40806c5f SHA-256: 55b572cfc7227b42f2185c0725c9d71eec4e6ef87ec99ec28f4196e55508137a
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely related to phishing or malware distribution via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

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 https://kcharp.com/ckfinder/userfiles/files/95546377028.pdf In PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/44537567407.pdfIn PDF document text
    • http://2990592.ru/ckfinder/userfiles/files/41700561385.pdfIn PDF document text
    • http://devitohomesorlando.com/userfiles/files/95605387685.pdfIn PDF document text
    • http://stonestudio.pl/files/upload/file/38751909292.pdfIn PDF document text
    • https://maintogelonline2.bet/contents/files/deturomezinekabogige.pdfIn PDF document text
    • http://briztravel.com/upload/files/wesarezilumomixorapewize.pdfIn PDF document text
    • http://www.medicellbank.com/userfiles/files/29671335710.pdfIn PDF document text
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1616042a9974aa---pobigadoretuxewitefaz.pdfIn PDF document text
    • http://cobmedia.hu/include/bulezogapos.pdfIn PDF document text
    • http://themetamorphoseprogram.com/userfiles/file/baroxewikolibuzele.pdfIn PDF document text
    • http://www.saito-ken.jp/userdata/file/90639947247.pdfIn PDF document text
    • http://clinicaveterinariabilancino.it/userfiles/files/xadirizukifis.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/1615d203d4781b---tijeva.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1615bf69d64492---78796520163.pdfIn PDF document text
    • http://chataigne-cevennes.fr/imgs/files/49733141909.pdfIn PDF document text
    • http://veszpremlizards.hu/_user/file/lonotemuzik.pdfIn PDF document text
    • http://marasintl.com/public/ckfinderuploads/files/46856023849.pdfIn PDF document text
    • http://girisimcilikproje.com/resimler/files/kopijatimedovujoxusu.pdfIn PDF document text
    • http://kuwaited.com/cote_dor_import/admin/ckfinder/userfiles/files/xusorakazul.pdfIn PDF document text
    • http://wideanglepackaging.com/ckfinder/userfiles/files/79997957028.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=keep+your+enemies+close+but+friends+closerPDF link annotation
    • https://www.thc.gda.pl/ckfinder/userfiles/files/73959574015.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_off0000e715.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE715 10964 bytes
SHA-256: 525f25c928b384aff654588212d3cdac9304d509f6491298e8046dd12b8a1d51
font_01_sfnt_off0001004e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1004E 21420 bytes
SHA-256: b02641b63e6ba08909af0a840fab34805978fd603f8d2dd608c64cab2534b6c2
font_02_sfnt_off000138a9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x138A9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1