Malicious PDF — malware analysis report

Static analysis result for SHA-256 9db6bd61aa039e79…

MALICIOUS

PDF

80.9 KB Created: 2021-08-08 13:49:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: e74fc6c8d90ca47779bc972019755a54 SHA-1: 28494ffd155d69cffcdcb2bd9acb13e3fa22cff3 SHA-256: 9db6bd61aa039e799266e00accab304fd9e8d309de461ff5185cc32e03e36013
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. The heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised CMS upload directories, suggesting an attempt to distribute further malicious content or phishing pages. The presence of multiple distinct hosts and disposable hosting patterns reinforces its role as a distribution mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9989

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/p7uh8hhokfdq3losefjqbhlf2s/tufuwame.pdf In PDF document text
    • http://www.nationaalgolfcongres.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160912779ad21d---vojegilog.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160cad2931fab4---70363766492.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a6847701859---borojubasixomejanedebi.pdfIn PDF document text
    • http://parzenica-bialka.pl/userfiles/files/85266633955.pdfIn PDF document text
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16077fdda3ebf2---93780571172.pdfIn PDF document text
    • http://gptools.net/userfiles/file/koduwabowerulagolewopapep.pdfIn PDF document text
    • http://ipceurope.com/assets/file/95245746069.pdfIn PDF document text
    • http://totalfinance.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16075b6fac2372---10843563247.pdfIn PDF document text
    • https://tempegaring.com/contents//files/2900825480.pdfIn PDF document text
    • https://www.infrascale.com/wp-content/plugins/super-forms/uploads/php/files/56b30636c96b8c38f7f9f41516d70ea7/nugasinefiwasenozim.pdfIn PDF document text
    • http://www.almansori-ye.com/almansorifiles/files/tazuzimo.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/j6fmh61fmntjhhs1ftj7u6jeu3/40265316969.pdfIn PDF document text
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/29069c2ea1eab42752efeade64717bc3/vukeb.pdfIn PDF document text
    • http://www.masozilina.sk/ckfinder/userfiles/files/vixeruvajuvetis.pdfIn PDF document text
    • https://okinawa4d.com/contents//files/levetada.pdfIn PDF document text
    • http://expertsystemgroup.com/file_media/file_image/file/jixovibewesalinugewunaku.pdfIn PDF document text
    • https://christembassyromford.org/wp-content/plugins/super-forms/uploads/php/files/b9fef564be7b4f8127f66a45af5f3dcc/futer.pdfIn PDF document text
    • http://iideree.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609a6a6047d6e---zodijuw.pdfIn PDF document text
    • https://www.scilights.com/wp-content/plugins/super-forms/uploads/php/files/a67bd5b146428e102dcb384f703d336e/riwazimekuzirelori.pdfIn PDF document text
    • http://qtjdb.com/UploadFile/2021/05/18/file/20210518_172719_159.pdfIn PDF document text
    • http://ytovietnam.net/ckfinder/userfiles/files/minagevesurofolik.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/34255163572.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e9161a8c090---6683502666.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=earth%27s+rotation+and+revolution+worksheet+answersPDF 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_off0000d701.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD701 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ef13.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF13 17280 bytes
SHA-256: b969e27cbd6c74651f250a1fb32c1220fe6dca992ea0fc6d8158b0047045ae8a
font_02_sfnt_off00011c83.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C83 10704 bytes
SHA-256: a111c2bc67cfe47e091119c65ac0a947e7b11c6868abc3e8d4503fcfe60ec651