Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3721dda4cb27f04…

MALICIOUS

PDF

83.9 KB Created: 2021-09-02 22:51:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 833908cf987c9daace53c318e8c656cf SHA-1: 18023fb78523ab14f92e787209873cfd8c556886 SHA-256: f3721dda4cb27f0472006c2410aaf8f6dee7644a12a070af016f3dfdc2320e62
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan payload. It contains numerous links to external websites, many of which are hosted on compromised or disposable domains, suggesting a link farm designed to redirect users to malicious content. The presence of a 'download button' heuristic further supports a lure-based attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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=checkstyle+eclipse+plugin+manual+install
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609572aeee9ff---muwupetumemikox.pdf
    • https://heritagecambodiatravel.com/userfiles/file/wemem.pdf
    • http://sun-eko.eu/files/file/fenavozowaxovazufaliguz.pdf
    • http://w-f-l.de/user_img/file/lezozit.pdf
    • http://www.hydro-tg.pro/upload/file/polepubodogaxufojiremaxu.pdf
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/5b4c5af0efd2cbe6293803477557e898/51957039938.pdf
    • http://patronusalapitvany.hu/public_html/upload/42348228942.pdf
    • http://olversonfamilyreunion.org/clients/5/51/51a48c89da211807e19ed56f8a1a1822/File/62333989204.pdf
    • https://f1com.ge/wp-content/plugins/super-forms/uploads/php/files/09a28221e23b5732e544e07daff67e66/tevakuperelatamamom.pdf
    • https://ascend.sut.ac.th/ce/2017/src/plugins/ckfinder/userfiles/files/64473105900.pdf
    • https://apoiotelecom.com/imagens/img_fckeditor/file/modetome.pdf
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16107c42d2bb19---gebob.pdf
    • http://moreit.ch/productinfo/file/96537280096.pdf
    • http://ahdongjiu.com/upload_fck/file/2021-7-26/20210726144222234808.pdf
    • http://hum-lucknow.org/test/fckeditor/file/57837884986.pdf
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160f2c14e13727---vitomopivakeb.pdf
    • http://slhospital.com/upload/fckeditor/file/bevixubakegikudupazos.pdf
    • https://valubil.com/public/uploads/cms_file/cms_files/zetotuge.pdf
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/56bafaa72b5c5b438b64687899c18b10/12513425401.pdf
    • https://www.sesc.com.ua/wp-content/plugins/super-forms/uploads/php/files/7l1smd4q8t08lkadpu1dqd18t5/bomivejuwoseziwagakabuze.pdf
    • http://asirius.su/wp-content/plugins/super-forms/uploads/php/files/2ee919e89e413726e4a326027a32f93d/sewixozarapivenebiwud.pdf
    • http://modelkyujin.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f1db47332f---30819647741.pdf
    • http://kazuma.ru/ckfinder/userfiles/files/vixadikemod.pdf
    • https://fenixfalt.com/userfiles/file/96200706907.pdf
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/160ba865f0e7b2---liligijisejediwamadu.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_off0000df03.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF03 16792 bytes
font_01_sfnt_off0000f715.bin
346b317da79294e3cbcd33e3c14bf98d4720136f674187bea8d383ea0b454232
pdf-font-stream PDF embedded font (sfnt) at offset 0xF715 19252 bytes
font_02_sfnt_off00012846.bin
49e233fd377107ac6a6d550780c8cd78fdcdb59f23d6747a591b7e8e23993d78
pdf-font-stream PDF embedded font (sfnt) at offset 0x12846 10940 bytes