Malicious PDF — malware analysis report

Static analysis result for SHA-256 598e5318f019e6fd…

MALICIOUS

PDF

72.4 KB Created: 2021-09-01 10:26:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 06ad0d8d378390f1f04d999c64ab8c68 SHA-1: 3ef3bf7de9896c5847d450ba1283754648401fb3 SHA-256: 598e5318f019e6fdab620a130c6cdb7e604264f60459ef71feb6f1355d30c669
156 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with numerous embedded URLs pointing to potentially compromised WordPress uploads and other disposable hosting sites. The primary attack pattern appears to be luring users to malicious content or phishing sites through these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://tourpon.kr/FileData/ckfinder/files/20210714_E238CB10E487B4D8.pdf In PDF document text
    • http://x-site.by/upload/editor/files/67800874017.pdfIn PDF document text
    • https://zemiigori.com/uploads/file/fogutivifoxabelezobaxuv.pdfIn PDF document text
    • http://kondicionery-shodnya.ru/upload_picture/file/3664718139.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/i2dk0h0jmram33j3b10krtu27o/zikabosamexi.pdfIn PDF document text
    • https://member-amz-seller-system.de/wp-content/plugins/super-forms/uploads/php/files/d4699bde4a4a29df86e84cd93c7a9793/43431379260.pdfIn PDF document text
    • http://romanakladatelstvi.cz/userfiles/file/wilavakozava.pdfIn PDF document text
    • http://steelbo.com/uploads/admins/u0/files/20210811180449.pdfIn PDF document text
    • http://dianacb.cz/userfiles/file/8317154506.pdfIn PDF document text
    • http://gazosilikatnn.ru/uploads/files/22437839032.pdfIn PDF document text
    • http://mcutech.net/files/zebowegulunadudup.pdfIn PDF document text
    • https://alhurwallpaper.com/Files/files/junolipogitubojovu.pdfIn PDF document text
    • https://familienbilstrup.dk/userfiles/file/zesalutuxewojekobivubut.pdfIn PDF document text
    • https://reflexlighting.com/wp-content/plugins/super-forms/uploads/php/files/1bf566fe703f6277823f226f59e417e4/3394965528.pdfIn PDF document text
    • https://confetti-seasons.ru/upload/files/97717904142.pdfIn PDF document text
    • https://www.drserapkagan.com/wp-content/plugins/super-forms/uploads/php/files/6dd19dh21dg0hm1bbooraqquqs/dositedugisab.pdfIn PDF document text
    • http://dichvuwebsites.com/media/ftp/file/26133723643.pdfIn PDF document text
    • http://www.lukoilmarine.com/ckfinder/userfiles/files/53342911075.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/a3c698f4589dfc57d3f690c6a0dad079/namokajifevefufabaxaragob.pdfIn PDF document text
    • http://grapes4u.ca/sites/all/sites/grapes4u.ca/files/xunemalevirotalasobevalo.pdfIn PDF document text
    • http://www.whirlpool-beachcomber.at/wp-content/plugins/formcraft/file-upload/server/content/files/16128172d9f26a---bejawevatiwesutusunoz.pdfIn PDF document text
    • http://www.garriagricola.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0d3c9e0aa4---subun.pdfIn PDF document text
    • http://gymostrov.eu/gymostrov/userfiles/file/52633250571.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=2010+census+population+by+statePDF 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_off0000bbc2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBC2 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d3d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3D4 14952 bytes
SHA-256: 65b6f4aefb5cf1f287a3530f2cf19eaaf3aa50b825cffda7da75325852dfeb59
font_02_sfnt_off0000f9a0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9A0 10820 bytes
SHA-256: 0858f119355aaec9cbac83724b110f097e9fb49796c7fb70c30b47ac6430d285