Malicious PDF — malware analysis report

Static analysis result for SHA-256 16b1edaf94a2451e…

MALICIOUS

PDF

70.1 KB Created: 2021-09-14 04:51:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 6e08957b5103bf3e4c3393013cc8fc85 SHA-1: 2e3f2404c01ef4fcf0fc32b3bffc7c27eb3f9c63 SHA-256: 16b1edaf94a2451e850f06e9be374e86fc3b215bda852043154c7d1f5174c5c3
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to multiple external websites, some hosted on potentially compromised or disposable domains. The presence of numerous links, including one pointing to a compromised WordPress upload storage, strongly suggests an attempt to distribute malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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://happycondo.leaddeehub.com/userfiles/files/91131117041.pdf In PDF document text
    • http://xn----itbbfrdrdbd4bgy6gi.xn--p1ai/webroot/files/files/nifebijusuvesodefopidaw.pdfIn PDF document text
    • https://optimuselearningschool.aels.edu/learning/site/images/uploadfiles/52919956795.pdfIn PDF document text
    • http://www.mbk-montage.nl/ckfinder/userfiles/files/penizivowuf.pdfIn PDF document text
    • http://kortennis.co.kr/B/ck/ckfinder/userfiles/files/80521425463.pdfIn PDF document text
    • https://sakura-bashi.com/uploads/files/202109021055108209.pdfIn PDF document text
    • http://zap-interactive.com/uploads/files/dewipurutepam.pdfIn PDF document text
    • http://www.tractortools.cz/ckfinder/userfiles/files/vajaj.pdfIn PDF document text
    • http://meyergarden.com/ckfinder/userfiles/files/lagepole.pdfIn PDF document text
    • http://hawaiianhunareiki.it/file/39803158433.pdfIn PDF document text
    • http://infinivideo.hu/sites/infinivideo/files/30326983052.pdfIn PDF document text
    • http://kajo-frings.de/userfiles/file/saruzorutubisugu.pdfIn PDF document text
    • http://israel-aliya.com/wp-content/plugins/super-forms/uploads/php/files/fcc4d76edfc065faf0346e5016f515d6/mavixunivutewobawefisab.pdfIn PDF document text
    • http://noahmission.org/dataroom/file/82836994050.pdfIn PDF document text
    • https://gilbertems.com/videos/file/lewuredepizesezuxivukor.pdfIn PDF document text
    • http://namadagaskare.ru/ckfinder/userfiles/files/kugopojit.pdfIn PDF document text
    • http://www.me.ntou.edu.tw/ckfinder/userfiles/files/20210902_151336.pdfIn PDF document text
    • https://matricula.netlandschool.cl/files/piwitoxotag.pdfIn PDF document text
    • http://joeun-it.com/userData/board/file/tidafuzebeboxilis.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/82bac79dd2e68787f7882216c84382ef/bovarazodagumawilibukusiw.pdfIn PDF document text
    • http://noithatsah.com/webroot/img/files/vekoleririgumifumixowejuw.pdfIn PDF document text
    • http://entone.es/wp-content/plugins/super-forms/uploads/php/files/925ff873cbd04846faf61fdf5d42ed94/53168441524.pdfIn PDF document text
    • http://nenayu.com/filespath/files/20210913123721.pdfIn PDF document text
    • http://agavietnam.com/img/files/69679011809.pdfIn PDF document text
    • https://qkon.ca/images/file/19519436793.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=3ds+max+apkPDF link annotation
    • http://cluster006.ovh.net/~greeters/namur/ckfinder/userfiles/files/69705657730.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_off0000b619.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB619 15168 bytes
SHA-256: b402c9b164bfc4079676745a6000ec0b852881f997a656c4aa353d38b9e6fe6d
font_01_sfnt_off0000dc4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC4E 10132 bytes
SHA-256: dddd1763e8e7c9f4e6d0ede0af14bb4711a1e04e00d4e8ce72f6aff82d90d4bf
font_02_sfnt_off0000f2ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2EF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1