Malicious PDF — malware analysis report

Static analysis result for SHA-256 9fb4a7684d196d02…

MALICIOUS

PDF

82.0 KB Created: 2021-09-05 09:07:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 753c0db7358653216caa1bf3941d0ab1 SHA-1: 1a268bd5e33afc80c75b0cbadcf533ba51859577 SHA-256: 9fb4a7684d196d021156e8e71d437295d6d77cda8da06b6b59f594a4d88286f4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file is identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are hosted on compromised CMS upload storage. The primary purpose appears to be SEO manipulation or directing users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://www.hinkler.com.au/application/third_party/ckfinder/userfiles/files/nudopipetasisakajinofixej.pdf In PDF document text
    • http://fanti-fitness.pl/uploads/assets/file/gutewavizubebedegatumufa.pdfIn PDF document text
    • http://hotelpenza58.ru/ckfinder/userfiles/files/58082881520.pdfIn PDF document text
    • http://fairview66.org/clients/866114/File/15308429412.pdfIn PDF document text
    • http://karthikeyanjayaram.com/userfiles/file/79370812083.pdfIn PDF document text
    • http://dolphinegypt.net/userfiles/file/17206889719.pdfIn PDF document text
    • http://teacherandtraining.com/coj_u/KK/userfiles/files/perazuzati.pdfIn PDF document text
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160707ca2b0a8f---18944692046.pdfIn PDF document text
    • http://dorp.pl/userfiles/files/96134839463.pdfIn PDF document text
    • http://bbpcosmetics.com/admin/upFiles/2021-5/file/govabovasusexofogiximi.pdfIn PDF document text
    • http://school15-tyumen.ru/f/4024514014.pdfIn PDF document text
    • http://cyklo-sport-servis.cz/UserFiles/File/16596920627.pdfIn PDF document text
    • https://elitteaccesorios.com/wp-content/plugins/super-forms/uploads/php/files/n1mtkscvi18k9g6bgo7gp30n3v/mowomaxarukuleralonezitog.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/fi07p25ndrskt9ur164oc2k9t3/zegor.pdfIn PDF document text
    • http://ofipapel.org//ckfinder/userfiles/files/vojezalo.pdfIn PDF document text
    • http://wskinbody.com/data/boardData/files/60797565096.pdfIn PDF document text
    • http://ayurveda-shiatsu-qigong-nice.com/upload/files/kidolasozo.pdfIn PDF document text
    • http://vasvaripalmuzeum.hu/upload/file/nugosenifuzidiruzinixofe.pdfIn PDF document text
    • https://indolabtek.com/Uploads/userfiles/files/74278520041.pdfIn PDF document text
    • http://discarga.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609cf730864e0---doxupozo.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c54b8948e32---xenibirutag.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/160a9e8ed3f54e---leminewafovalisiwosego.pdfIn PDF document text
    • http://roocenter.ru/upload/file/lidurikepudanezu.pdfIn PDF document text
    • http://www.dismaplant.com/ckfinder/userfiles/files/24498190270.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160cef5c4c8368---nekajowejokumibulutig.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=english+folk+song+suite+saxophone+pdfPDF 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_off0000d4fe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD4FE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ed15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED15 10952 bytes
SHA-256: e13689bd2985c7ab9cc09cbc8330e0433efc97035ed10fcacb604dcceba506ca
font_02_sfnt_off00010639.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10639 20384 bytes
SHA-256: 27cbcff3b68ef799e916dd04c513b6dcd6fa915ceebfea2fa573f0d086c14156