Malicious PDF — malware analysis report

Static analysis result for SHA-256 37543a5c7e42170f…

MALICIOUS

PDF

83.9 KB Created: 2021-09-18 10:04:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: f4578f376f22c9360b6a34e49b78fc6d SHA-1: 531d0e8118f3767120195f098a9e205a5fa9a3b5 SHA-256: 37543a5c7e42170fb185384cbc7ee1b2d99a92788366b29ac6181fc7d3d9f355
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The PDF contains numerous embedded URLs, with one specifically pointing to 'infrive.ru' and containing a 'vice+city+unlimited+money' UTM term, suggesting a lure for potentially fraudulent content or phishing. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further supports that the document is designed to host many links on disposable domains, a common tactic for distributing malware or conducting phishing campaigns.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://infrive.ru/uplcv?utm_term=vice+city+unlimited+money PDF link annotation
    • https://careerroots.net/ckfinder/userfiles/files/27534228966.pdfIn PDF document text
    • http://bridgestone-ice-cruiser-7000.ru/ckfinder/userfiles/files/vidufovafe.pdfIn PDF document text
    • https://kaptenhoki.net/contents/files/34447334311.pdfIn PDF document text
    • https://cs-nippon-cp.com/mailmagazine/upload/files/61358085042.pdfIn PDF document text
    • https://dreamscapes.ca/dream_scapes/userfiles/files/rivumaliwivedodaxar.pdfIn PDF document text
    • http://htwy.com/upload/file/91050915405.pdfIn PDF document text
    • http://frutapac.com/ckfinder/userfiles/files/biluvupixabinafiso.pdfIn PDF document text
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614537aae04f0---wekogefajoj.pdfIn PDF document text
    • https://aparcaderoshaddaichile.cl/uploads/images/files/dutopukazemegoxavipifume.pdfIn PDF document text
    • https://jamurgoreng.net/contents/files/fewudesujasemuvizemoro.pdfIn PDF document text
    • http://bocghedanang.com/media/ftp/file/vatedalofoxatojosixi.pdfIn PDF document text
    • http://www.jasolasia.com/image/upload/File/pizotizulinatezixubera.pdfIn PDF document text
    • http://www.salac.cz/ckfinder/userfiles/files/nolozigupakukim.pdfIn PDF document text
    • http://dungcubepgiangtrinh.com/webroot/img/files/kokozedewux.pdfIn PDF document text
    • http://ichieh.tw/uploads/files/202109171831098195.pdfIn PDF document text
    • http://skrutit-probeg.ru/upload_picture/file/jawakisigelivuvufitu.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612efbf11daeb---57151146809.pdfIn PDF document text
    • https://lrsinc.co/userfiles/file/75184052307.pdfIn PDF document text
    • http://cn-biyoute.com/d/files/85118378259.pdfIn PDF document text
    • http://888spirits.com/userfiles/file/86484416021.pdfIn PDF document text
    • http://kcemsp.org/upload/editor/file/80333029159.pdfIn PDF document text
    • http://esejsc.com/upload/files/sowotegobifovisub.pdfIn PDF document text
    • http://pwr-tech.ru/userfiles/file/86821373420.pdfIn PDF document text
    • http://videlec.be/ressource/file/93637555258.pdfIn PDF document text
    • https://auditorescr.com/ckfinder/userfiles/files/tumilovepuserunofajal.pdfIn PDF document text
    • http://parentini.it/userfiles/files/28791566837.pdfIn PDF document text
    • http://live-lessons.net/lcj/web/uploads/assets/file/39290728541.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_off0000e63b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE63B 16988 bytes
SHA-256: 01646f5374214531d7ca8b1381f6101ecccca218a7d1dce4ecb1198181e14e60
font_01_sfnt_off0001124b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1124B 10284 bytes
SHA-256: 24b6ae152aed2d9d8c40a5519851753efe5c95085e87a94df56088c60fe658bc
font_02_sfnt_off00012970.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12970 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1