Malicious PDF — malware analysis report

Static analysis result for SHA-256 15a541afea1a06d0…

MALICIOUS

PDF

77.6 KB Created: 2021-09-13 21:13:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: b270e63d60aec74763c0a3db123a3bf4 SHA-1: 15436e93099ac9eb23944241e493ceb1f4dd16bf SHA-256: 15a541afea1a06d07f08dcefa7f326e564064b299d21d838c44aaae2e7bac202
156 Risk Score

Malware Insights

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

The PDF file contains a link farm pointing to multiple domains, some of which are hosted on compromised CMS uploads or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded URLs suggest an attempt to redirect users to external, potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9829

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 http://kronikarp.pl/ckfinder/userfiles/files/87620837484.pdf In PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/0ea81478b81673896b5ab2b738162f07/kekiji.pdfIn PDF document text
    • http://isleford.com/filespath/files/20210904200003.pdfIn PDF document text
    • https://yptea.com/data/fckeditor/files/zexipemuvapabowa.pdfIn PDF document text
    • http://randoquad72.fr/userfiles/file/pozizisenenil.pdfIn PDF document text
    • http://servis-hradec.cz/files/file/nadugivekifafininam.pdfIn PDF document text
    • http://fabrykakonwersji.pl/wp-content/plugins/super-forms/uploads/php/files/a06fd7beae84117b62dbe260d17bc1dd/sopubefoz.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/files/38801750211.pdfIn PDF document text
    • http://lesmashclub.com/imgUpload/files/41416255044.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b3d065c064---16089140371.pdfIn PDF document text
    • https://machnik.net/ckfinder/userfiles/files/80715927198.pdfIn PDF document text
    • https://kingwrapcarspa.com/upload/files/buvajoferimaruzukevegazoj.pdfIn PDF document text
    • http://potentialdesign.cn/userfiles/file/1630551086.pdfIn PDF document text
    • http://singer-island-condos.com/userfiles/files/44822139559.pdfIn PDF document text
    • http://camberwelltaxi.com/survey/userfiles/files/19638272302.pdfIn PDF document text
    • http://medicaldistri.com/ckfinder_files/files/80431856361.pdfIn PDF document text
    • http://leprofit.ee/cmsfile/contentfiles/dojuse.pdfIn PDF document text
    • http://imailbox.nl/images/uploadedimages/file/buvuweberudizizik.pdfIn PDF document text
    • http://fatename.com/uploads/files/202109060431475658.pdfIn PDF document text
    • https://lenaoyunlar.com/calisma2/files/uploads/fekaz.pdfIn PDF document text
    • http://szjwwj.com/userfiles/file///55876162127.pdfIn PDF document text
    • http://mcutech.net/upload/2021/09/file/1630559048111907383.pdfIn PDF document text
    • http://xn--9w3b11kh5l.com/ckupload/files/7299304666.pdfIn PDF document text
    • http://fotografieindex.nl/images/uploads/61951515647.pdfIn PDF document text
    • https://rentcar888.com/uploads/files/202109110213204423.pdfIn PDF document text
    • http://h-st.nl/bestanden/files/jixenijikavefa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=extreme+car+drivingPDF 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_off0000cbc8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCBC8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000e3da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE3DA 17460 bytes
SHA-256: 4122abbec08ff4cb73f4aa16de94c7de6669bead81e83d1389f2d532669511c9
font_02_sfnt_off0001112c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1112C 10528 bytes
SHA-256: a1a7b3968ad7d747693c5085c5304726673219794a4e47aa0a0a3f11b6ce3fcb