Malicious PDF — malware analysis report

Static analysis result for SHA-256 c3089e27d2450be2…

MALICIOUS

PDF

86.9 KB Created: 2021-09-14 01:48:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 4e43f3b43f8989900c40a6e565b9eb38 SHA-1: 89ea8e4be072ec41e8ca034761099b66f3cd6ce4 SHA-256: c3089e27d2450be2b2e6cd8bfe7c9aa2bc5d8e47a33042b59f50870cfd1841e8
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to other PDF files hosted on various domains, many of which appear to be compromised or disposable. This structure strongly suggests a link farm designed to distribute malicious content or facilitate phishing attacks. The ML classifier and ClamAV detection further confirm the malicious nature of this PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://krisoc.ru/uplcv?utm_term=watch+latest+films+online+free PDF link annotation
    • http://paykaaluminiya.ru/ckfinder/userfiles/files/66650649465.pdfIn PDF document text
    • http://svs-pm.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138d45314db0---pukatukudewuvetopedusilon.pdfIn PDF document text
    • http://eastcoastbiker.de/sites/default/files/file/kedawo.pdfIn PDF document text
    • http://nissanotogovap.vn/uploads/images/files/kitezeguxe.pdfIn PDF document text
    • http://hanifeugur.com/image/files/61618971964.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/4ba80b5fe2b2b0dbfd430fe3d72db190/57623912947.pdfIn PDF document text
    • http://hdg-gmuend.de/userfiles/files/7314828400.pdfIn PDF document text
    • http://tafgambiatours.com/userfiles/file/konuw.pdfIn PDF document text
    • http://balmybnb.com/t/tutorfirm/uploads/ck/files/27168251478.pdfIn PDF document text
    • http://centroolosprato.it/userfiles/files/28629537870.pdfIn PDF document text
    • https://rubin2000-distribuitorshop.ro/userfiles/file/komifoxeripi.pdfIn PDF document text
    • https://basealimentare.it/webroot/files/fck_uploads/File/43231204890.pdfIn PDF document text
    • https://stauber.lt/images/files/15743342050.pdfIn PDF document text
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/a9d545219623c86ea20435a7f51e4d70/74279226599.pdfIn PDF document text
    • https://vegastel.eu/components/com_mijoshop/opencart/image/data/files/nurosulogazagezurad.pdfIn PDF document text
    • http://synerfreight.com/syner_upload/images/files/guzisunesinu.pdfIn PDF document text
    • https://autopsrus.aerovents.com/ckfinder/userfiles/files/16237623303.pdfIn PDF document text
    • http://infrabud.eu/fckpliki/file/29029651952.pdfIn PDF document text
    • https://smgbid.com/ckfinder_userfiles/files/66998362673.pdfIn PDF document text
    • http://fosterfreezesantarosa.com/uploads/files/pipaxarozuloroze.pdfIn PDF document text
    • https://bwhe.in/ckfinder/userfiles/files/mupupu.pdfIn PDF document text
    • http://mfahk.com/upload/files/wujofuvotefoj.pdfIn PDF document text
    • http://shlawllc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/27842654383.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_off0000ef9b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF9B 17924 bytes
SHA-256: 23f9032f4cf54d6b4841e811c650c96d091d98a152e0364a54b594d541be604f
font_01_sfnt_off00011dbd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11DBD 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000135d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x135D4 10596 bytes
SHA-256: 3d90021b9f05040f1f630faf95803aa7040b588bc0e1aad67ef95d716eaad75f