Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdb6274147a73f1b…

MALICIOUS

PDF

83.0 KB Created: 2021-09-11 08:04:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 5bb43586b4a6debcd55323baa7b5459b SHA-1: 3953d8f91d2b6c6b3b9d7102bfea480d9e54a275 SHA-256: cdb6274147a73f1b05afeea25fb7cd5c87f47201772599181b09d69556c15ea4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm with numerous URLs, many pointing to compromised CMS uploads, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent. The presence of multiple external URIs and link farm heuristics further supports this assessment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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 http://fsnmmaterials.com/UPFILE/userfiles/files/kinulonizaxoxemufonere.pdf In PDF document text
    • http://sangjeom.com/userfiles/file///26248633386.pdfIn PDF document text
    • http://bigbulkbags.ahmadpackages.com/survey/userfiles/files/49915339919.pdfIn PDF document text
    • http://skpizzasubs.com/uploads/files/24049688643.pdfIn PDF document text
    • https://wonwon.taipei/photo/file/90890916668.pdfIn PDF document text
    • https://iasvn.org/Images_upload/files/50660936658.pdfIn PDF document text
    • http://www.nanodrywash.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139139399734---sigaxekofineb.pdfIn PDF document text
    • http://fotostudiovaccari.it/userfiles/files/42758192927.pdfIn PDF document text
    • http://coffee33.ru/archive/file/35433315390.pdfIn PDF document text
    • http://maxitelt.no/wp-content/plugins/formcraft/file-upload/server/content/files/16138fed366fe9---16329403321.pdfIn PDF document text
    • http://www.protectakoteasia.com/ckfinder/userfiles/files/linujebexukutisibo.pdfIn PDF document text
    • https://hung168.tw/UserFiles/files/disukabonadetul.pdfIn PDF document text
    • http://tacchigroup.com/public/thread/risorse/file/93053530068.pdfIn PDF document text
    • http://wwsm-hk.com/files/file/satixadukepinanija.pdfIn PDF document text
    • http://www.ntweac.edu.hk/admin/ckfinder/userfiles/files/91476764657.pdfIn PDF document text
    • http://leicesterbiketec.com/userfiles/file/zusivoxabebapevime.pdfIn PDF document text
    • https://onderdurdu.com/upload/ckfinder/files/5524366685.pdfIn PDF document text
    • http://sloplast.com/userfiles/files/rimafolofu.pdfIn PDF document text
    • http://chipgene.com/image/files/20210901_223408.pdfIn PDF document text
    • https://www.zaantraining.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16133210779202---31124556100.pdfIn PDF document text
    • https://sakura-bashi.com/uploads/files/202109081248315065.pdfIn PDF document text
    • https://gilbertems.com/videos/file/mabimewesawumigav.pdfIn PDF document text
    • http://www.ortodonciaelisafarache.com/ckfinder/userfiles/files/gerunepujejunezin.pdfIn PDF document text
    • https://curvy.tw/upload/files/75717501377.pdfIn PDF document text
    • https://sadex.pl/fck/file/rasusixovalus.pdfIn PDF document text
    • http://gomsuhoangminh.com/app/webroot/uploads/files/vokegeripapafaxoxovazide.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=mini+tv+for+android+mk808b+plusPDF 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_off0000dcf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDCF2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f509.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF509 11248 bytes
SHA-256: 717b25a38f1c0a3087e575f73defe0c26e986cf23505705353d5e7a553c2c431
font_02_sfnt_off00010f2a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F2A 18172 bytes
SHA-256: b93cbd15e1dc09cfbcb2c1d91f0e899ab927ad7c800e802efd5c53d05082efa0