Malicious PDF — malware analysis report

Static analysis result for SHA-256 9e540672055d65ef…

MALICIOUS

PDF

83.9 KB Created: 2021-09-19 05:56:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: 22e77abb5723127a17a0127ac2722f38 SHA-1: a989a15d5eb693cfb6c3bd1b7774e493fef11235 SHA-256: 9e540672055d65ef3d40ea5609b0bf00dc56c9c2007e045d106279e1231a1b0d
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, several of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate maliciousness, with ClamAV identifying it as a phishing trojan. The file's structure and embedded links suggest it's designed to lure users to malicious sites, likely for credential harvesting or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://www.gurgy.net/ckfinder/userfiles/files/81202515541.pdf In PDF document text
    • http://22vek-omsk.ru/fck_editor_files/files/zobemusokasifujuwisi.pdfIn PDF document text
    • https://5ky13lu3-1251.com/contents/files/82312266459.pdfIn PDF document text
    • http://kolbiko.com/images/uploads/file/68756961702.pdfIn PDF document text
    • http://at2apigroup3.com/contents/files/54794834327.pdfIn PDF document text
    • https://hagabb.ro/ckfinder/userfiles/files/19254007754.pdfIn PDF document text
    • http://photou.cc/ckfinder/userfiles/files/68307910312.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/fc53dbbd2465a6461ac4745a7095ecda/93856234097.pdfIn PDF document text
    • http://gazetavk.ru/img/file/madaxuzikegagezorotif.pdfIn PDF document text
    • https://crossfitbeeshark.ro/app/webroot/files/userfiles/files/fugazu.pdfIn PDF document text
    • http://rrmkaryacollege.org/rrmkarya/userfiles/file/zugiwafazewagubivivada.pdfIn PDF document text
    • https://jingchengs.com/jingchengs/ckfinder/files/20210905100824.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614050ef27f8e---solujorewoxe.pdfIn PDF document text
    • http://ipllaser.in/uploads/95603660444.pdfIn PDF document text
    • https://kotata-zlin.cz/obr/clanky/file/fakojitugurelivizixa.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/s5lrhq47ni0npcutp91618ag91/bukemitovizek.pdfIn PDF document text
    • https://allcreaturesinc.com/files/files/91064604058.pdfIn PDF document text
    • http://nextlab-semi.com/files/fckeditor/file/51794100016.pdfIn PDF document text
    • http://harringtonassociateslaw.com/Test/JabzMedicalBillingService/userfiles/file/39613473578.pdfIn PDF document text
    • http://taixingchem.com/uploadfile/file/20210916173717193.pdfIn PDF document text
    • http://stacjaregeneracja.pl/userfiles/file/fitefuwa.pdfIn PDF document text
    • https://eetravel.net/file/52099912830.pdfIn PDF document text
    • https://lighthousemacau.com/html_upload/file/musiresefuzanixopoge.pdfIn PDF document text
    • https://ndmoyun.com/calisma2/files/uploads/konixiropidasufalitibuv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=tom+and+jerry+giant+adventure+full+movie+in+tamilPDF 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_off0000de50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE50 10900 bytes
SHA-256: 1ff04045f0144d44dfa8a4eb88c8ef0169ea590e5e3e72ab441c75b082824b78
font_01_sfnt_off0000f744.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF744 19184 bytes
SHA-256: c0bd5add0dac940d976059cc8dffdbc2f7846eea0889ff127a327b0015f12a3c
font_02_sfnt_off00012951.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12951 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1