Malicious PDF — malware analysis report

Static analysis result for SHA-256 e831241efe2cb9b2…

MALICIOUS

PDF

71.2 KB Created: 2021-09-12 23:24:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 8638b8cd3c72105d4721fbdc029c413d SHA-1: f3f440ee9e78bdcf6942c50bcbd860804f9c54a2 SHA-256: e831241efe2cb9b278885565ea9190d4140ec209f49ea92c2aa843a8c2357ea5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The ML classifier and ClamAV both flagged this PDF as malicious, with ClamAV specifically identifying it as a phishing trojan. Heuristics indicate the PDF functions as a link farm, directing users to multiple potentially compromised or disposable hosting sites. The presence of embedded URLs and the nature of the heuristics strongly suggest an attempt to redirect users to malicious content, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://stellar.ru/ckfinder/userfiles/files/98353715346.pdf In PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613c5c53895cf---jatobavowajuxevenakosu.pdfIn PDF document text
    • https://kocgrafikavukatwebsitesi.demowebsiteleri.com/upload/files/tabikudeluzami.pdfIn PDF document text
    • http://dydlhx.com/upfiles/file///20507739554.pdfIn PDF document text
    • https://istanbularicilikfestivali.com/upload/ckfinder/files/24532826299.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/49fa40b3087c433f25e738fcd71e9e83/80865592696.pdfIn PDF document text
    • http://amicissiapiemonteisa.it/userfiles/files/42524278494.pdfIn PDF document text
    • https://clinicaabrahaoosta.com.br/ckfinder/userfiles/files/difen.pdfIn PDF document text
    • http://medicaldistri.com/ckfinder_files/files/koduzuvuvomav.pdfIn PDF document text
    • https://bbensonmft.com/wp-content/plugins/super-forms/uploads/php/files/335fd131db82857fa202d31a16d1e8c4/fomijukokevajawajevorovij.pdfIn PDF document text
    • http://pscworld.eu/ckfinder/userfiles/files/92960072769.pdfIn PDF document text
    • http://atthaya.com/file_media/file_image/file/47475244283.pdfIn PDF document text
    • https://slide-bearing.com/d/files/39464653707.pdfIn PDF document text
    • https://study-abroad-travel.com/ckfinder/userfiles/file/vemetemugifuraxafuluguxu.pdfIn PDF document text
    • http://coimbra.hu/uploads/ckfinder/userfiles/files/66816327169.pdfIn PDF document text
    • http://compie.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1613103b504d9e---67311873924.pdfIn PDF document text
    • http://hoitruyengiaocodocvietnam.com/uploads/image/files/95839038931.pdfIn PDF document text
    • https://turismopontevedra.com/ckfinder/userfiles/files/96644603323.pdfIn PDF document text
    • http://fk-fudosan.1nino3.com/app/webroot/img/userfiles/files/64003343417.pdfIn PDF document text
    • http://kursadowicz.pl/Upload/file/pivodabekunakafofuge.pdfIn PDF document text
    • http://aldobini.it/userfiles/files/55581354702.pdfIn PDF document text
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/26549387083.pdfIn PDF document text
    • http://nbmounts.com/userfiles/file/1631396039.pdfIn PDF document text
    • http://toanlinh.vn/upload/files/luvuwozojenazuruxud.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=bigg+boss+13+episode+7+full+episodePDF 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_off0000b53e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB53E 16124 bytes
SHA-256: 14cad9201b4e274628c625b80c965c03b952a38719c2c2e38c34e053c4988628
font_01_sfnt_off0000de6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE6C 10776 bytes
SHA-256: 32776e5fbbcfcda1f1ab6bf11f2511aba4aa788b597ce031ac1173f1a4bd8798
font_02_sfnt_off0000f70f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF70F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1

Open this report in the interactive analyzer, or submit your own file for analysis.