Malicious PDF — malware analysis report

Static analysis result for SHA-256 d2bf02359d7f40a0…

MALICIOUS

PDF

72.0 KB Created: 2021-09-08 18:24:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a25a589f078df700b88a42e13e2fa8cc SHA-1: 6a04f4f173c624f3391aef6a090f24ab9cec9dc4 SHA-256: d2bf02359d7f40a05c795623f82f10614cd6563946824ceaeeac6a85b4ec2875
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. Numerous heuristics indicate it functions as a link farm, directing users to various external websites, some hosted on compromised CMS platforms. The embedded URLs, such as 'https://cructi.ru/uplcv?utm_term=translating+algebraic+equations+worksheets+pdf', are likely used to distribute further malicious content or phish for credentials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

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://cructi.ru/uplcv?utm_term=translating+algebraic+equations+worksheets+pdf
    • http://seidels-mineralienwelt.de/images/uploaded/file/21969843418.pdf
    • http://coumert.com/images/file/vujewo.pdf
    • http://autolavaggiocraparotta.it/userfiles/files/fanizisuzurutagopaxuvug.pdf
    • http://dooroc.com/tk/upload/file/duvizepokejosodajoxu.pdf
    • http://www.sana-anong.com/ckeditor/ckfinder/userfiles2/files/7620460188.pdf
    • http://apartamentykunickiego.pl/architekci/public/upload/ckfinder/userfiles/files/41811454139.pdf
    • http://www.canadiantreasurer.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613671db895d1---4795308275.pdf
    • http://bagiez.com/userfiles/file/bufatibinasinusijum.pdf
    • https://handinhand-daycare.com/ckfinder/userfiles/files/39628372695.pdf
    • http://mixline.ru/img/lib/file/27705311453.pdf
    • http://www.investinwielkopolska.pl/application/lib/ckfinder/userfiles/files/wuvuvarogaxafobowaz.pdf
    • http://lideparts.com/userfiles/file/1631056302.pdf
    • https://floridagreatescape.com/media/file/misosubavugo.pdf
    • https://www.guestquesttravelmedia.com/wp-content/plugins/super-forms/uploads/php/files/04afuci5i5b5eqil79avuh5sj0/60654406618.pdf
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/5c7f9f97f6825cc7d360463b473a5b6a/82888498751.pdf
    • http://thebrownbag.vn/upload/files/guwudutumixijawugapapuka.pdf
    • http://pnmanagementsolutions.in/uploads/nebezoko.pdf
    • https://nisahanpin.com/calisma2/files/uploads/8366538662.pdf
    • http://purepoem.com/resource/docContentImg/file/2021-09-03/a977fd677051e591ee874e1227131130.pdf
    • http://cecev.com/stockages/files/14964202514.pdf
    • https://snoman.mb.ca/ckfinder/userfiles/files/rikuxixuw.pdf
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/b46dd6a7a237c2e7b9381332bb6b974c/bisosufemefun.pdf
    • https://kclandscapes.com/ckfinder/triplebuserfiles/file/70878589208.pdf
    • http://wadsoda.com/UserFiles/File/53330210746.pdf
    • https://www.champagne-auge-dascier.com/ckfinder/userfiles/files/taxotuxaraxugibuvifa.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/50e63e5c100ca543ece46dd210babd52/38018451045.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_off0000b8ae.bin
3ce5aefbb7375f9b37401651e1759d0dcd915b1bcd66cd56fef4739b2c9089cf
pdf-font-stream PDF embedded font (sfnt) at offset 0xB8AE 15376 bytes
font_01_sfnt_off0000dfe8.bin
2c2545dbac76203fe18363678ac2699e0d9de7178e3f631e0aa1f6a55e942f03
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFE8 11424 bytes
font_02_sfnt_off0000fa2b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFA2B 16792 bytes