Malicious PDF — malware analysis report

Static analysis result for SHA-256 d925d9e82eabce83…

MALICIOUS

PDF

78.9 KB Created: 2021-09-16 12:05:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 198e412dcba97bf0980aa83865e18bfa SHA-1: bfafd403b648f921b10b552f5a6eb81e7574dabc SHA-256: d925d9e82eabce83e17bcd6a04de610fd2a418a7953c89d54eabf055a55797e2
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many pointing to compromised WordPress upload directories or disposable hosting, indicative of a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery via these external links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://coretry.ru/uplcv?utm_term=anime+backgrounds+for+android
    • http://khonggianxua.samdigroup.vn/app/webroot/upload/files/tisizosutebis.pdf
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613c70aa22ceb---25222556912.pdf
    • http://solee.cn/ckfinder/userfiles/files/vasagexukadudivisi.pdf
    • http://talentfuturesservices.com/sharpinstitute/images/files/13669852724.pdf
    • http://eco-versute.com/app/webroot/ckfinder/userfiles/files/zepexivedo.pdf
    • https://www.gryf-wet.pl/ckfinder/userfiles/files/fazivurafeni.pdf
    • https://valserve.in/web/k/main_admin/ckfinder/userfiles/files/mubibejerikopaguwurol.pdf
    • http://palestraarkadia.it/userfiles/files/petopomudegegolu.pdf
    • http://tootingtaxi.com/survey/userfiles/files/pugujopek.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/161341a7bb9d7b---64702062079.pdf
    • https://glozor.com/userfiles/file/xutev.pdf
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140c37d9cb5c---18697805081.pdf
    • https://misbahelmudii.org/ckfinder/userfiles/files/84347476981.pdf
    • http://xn----otbb6ahq3d.xn--p1ai/ckfinder/userfiles/files/nerotozubumobapejevi.pdf
    • http://gioithieu.btccorp.vn/uploads/files/88962255890.pdf
    • https://larioenergy.net/uploads/file/38656263919.pdf
    • https://derfo.info/resimler/files/xefizadumo.pdf
    • http://fge-service.com/userfiles/file/60220814593.pdf
    • http://k2plusinterior.com/userfiles/16484172563.pdf
    • https://optimuselearningschool.com/learning/site/images/uploadfiles/45447445256.pdf
    • https://afayl.com/userfiles/file/18800955098.pdf
    • http://studioaba.net/userfiles/files/40348291304.pdf
    • http://delta-serwis.pl/pliki/nifizilibojejewitatesibe.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ce84.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCE84 16792 bytes
font_01_sfnt_off0000e69b.bin
9eac94f8f650ea704bb2143a964ad94a56ade753ff0d7bb4ccb6d73787903da0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE69B 10988 bytes
font_02_sfnt_off0000ffeb.bin
0c6b176b9995a2ca107e2b0a037ca87754c22f3725fc0fdde6b34eecf0322682
pdf-font-stream PDF embedded font (sfnt) at offset 0xFFEB 17760 bytes