Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd525cfd88364b72…

MALICIOUS

PDF

71.1 KB Created: 2021-09-22 16:23:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: e80f5f712a0a0368c4ef6f4f4e96cee9 SHA-1: a62d3ae61075c8f92ad9fcfdee7afedbdb9e03da SHA-256: cd525cfd88364b7202e1b8d9d4c4421f27f024303e45f9f851f12b7b24fefd74
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ClamAV as a phishing trojan and a machine learning classifier indicated a high probability of maliciousness. It contains numerous embedded URLs, many of which point to compromised CMS uploads or are part of a link farm strategy. The primary function appears to be redirecting users to potentially malicious content hosted on various domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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 http://ngocminhcnc.com/demo_thietbimay_24_7/upload/files/63139524900.pdf In PDF document text
    • http://mstreatmentadvances.com/userfiles/files/61157598693.pdfIn PDF document text
    • http://archpiudue.com/userfiles/files/podovijavazuwet.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/ade9c572905ee2c6ab24b7e11a4253bc/pogowiruviporananozonixe.pdfIn PDF document text
    • http://knx-shop.ru/admin/ckfinder/userfiles/files/50711393019.pdfIn PDF document text
    • http://cabanagarden.hu/editor_up/wufujudugadurotegowenagol.pdfIn PDF document text
    • http://yaqeen-eg.com/userfiles/file/pikafavumonivu.pdfIn PDF document text
    • https://mintedimages.com/ckfinder/userfiles/files/vegagogade.pdfIn PDF document text
    • http://swancentive.com/cote_dor_import/admin/ckfinder/userfiles/files/60244188934.pdfIn PDF document text
    • http://thriftstorewebsites.net/flash/thriftstorewebsites.net/file/jurabafelapibikuvaf.pdfIn PDF document text
    • http://irk-yoga.ru/upload/files/61281229679.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.org/upload/files/84810814126.pdfIn PDF document text
    • http://kuresi-kaitori.com/upload/content_pic/files/rixaganokoliridej.pdfIn PDF document text
    • http://bettynblue.com/upload/fck_img/20210903/file/fojojojewoda.pdfIn PDF document text
    • http://asorokolaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/parogijunefufaxiwazitamu.pdfIn PDF document text
    • http://sanmorales.es/userfiles/files/2530720241.pdfIn PDF document text
    • http://heilpraxis-pankow.de/wp-content/plugins/formcraft/file-upload/server/content/files/161410ce4955f6---95057091262.pdfIn PDF document text
    • https://jpjplumbingandheating.com/FCKeditor/file/15867763182.pdfIn PDF document text
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/ep385t252isgoru7ul027bhor7/41280590823.pdfIn PDF document text
    • http://indianspringhomes.com/userfiles/files/48064664279.pdfIn PDF document text
    • https://jasz-pap.hu/UserFiles/file/88841634913.pdfIn PDF document text
    • http://novena99.com/uploads/files/202109030452072134.pdfIn PDF document text
    • https://daqing-jewelry.com/uploads/files/202109161900286246.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/beriretajekofigexorawine.pdfIn PDF document text
    • http://sportsgarten.com/editorData/file/viwixunagakunumiw.pdfIn PDF document text
    • http://ikhmongol.mn/ckfinder/userfiles/files/18488772864.pdfIn PDF document text
    • http://pincailight.com/zk/UploadFile/file/2021092007474973499.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=serious+sam+2+game+download+for+androidPDF 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_off0000b74f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB74F 14976 bytes
SHA-256: 8d9d3989aba7208047bf01f24db1828f3cc1776540906ccef5d501188d6ec55d
font_01_sfnt_off0000dd32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD32 10980 bytes
SHA-256: 234f05a4c22b2c41e37f4715bab081a85ab2a30b9e367587ce385b29f1e9230e
font_02_sfnt_off0000f690.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF690 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1