Malicious PDF — malware analysis report

Static analysis result for SHA-256 c376e71369f6a85d…

MALICIOUS

PDF

74.0 KB Created: 2021-09-09 08:02:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: c9361c747b982d6787da196007f7194a SHA-1: be80798bd885e9de5feb6247aa67354d7a515b06 SHA-256: c376e71369f6a85d86af83f4da3d160c2e204ff1bbd37e2316291b9731870ba7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm used for phishing or malware distribution. The PDF structure and embedded links are consistent with a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.johnrealestate.in/ckeditor-ckfinder-integration/uploads/files/93984970810.pdf In PDF document text
    • http://sprostredkovanieuverov.sk/res/file/xifobeji.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16134138e202fd---82336089618.pdfIn PDF document text
    • https://alsharqcc.com/userfiles/files/totitizerala.pdfIn PDF document text
    • http://tinavaron.com/ckfinder/userfiles/files/tugoxamezejesutena.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/161370a8bcdd22---wopomubafuwedej.pdfIn PDF document text
    • https://brillimet.com/uploads/files/202109011514061635.pdfIn PDF document text
    • http://gloria-eurex.com/images/blog/file/depalusopuregarumi.pdfIn PDF document text
    • https://toppelletmachine.com/d/files/bilofazov.pdfIn PDF document text
    • http://metrocars.london/survey/userfiles/files/basasakonogirazagomab.pdfIn PDF document text
    • https://teplitsyoptom.ru/wp-content/plugins/super-forms/uploads/php/files/648653da5e08197fd1e77f61d0662534/zuwemowodo.pdfIn PDF document text
    • https://el-tall.pl/pics/file/netagajulexo.pdfIn PDF document text
    • http://salamatekhanevadeh.ir/ckeditor/files/files/94954153160.pdfIn PDF document text
    • http://testplanet.nl/uploads/files/28174249832.pdfIn PDF document text
    • http://antonio-pelella.eu/userfiles/files/diromafazajiwel.pdfIn PDF document text
    • http://www.ppk-kp3k.kkp.go.id/ver2/extra/ckfinder/core/connector/php/media/ckfinder/files/25619817413.pdfIn PDF document text
    • https://sunridgecorp.com/uploads/files/202109020149396804.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/eo2qllg4gfqbkb9hv87l8f6s36/29938939375.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/e40e3bb5464f08d47a8ed226f9e81dc3/biwopivotazosiziwa.pdfIn PDF document text
    • https://fsreloading.com/userfiles/files/vibajutizisafibuloti.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/16133441c4d880---47372899021.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/nagozekexirosujugutefenem.pdfIn PDF document text
    • http://marsalanoleggio.it/userfiles/files/gekexosuzipaje.pdfIn PDF document text
    • http://deauville.ru/files/file/puravojuxapevajadaxav.pdfIn PDF document text
    • http://strandedtattoo.net/file/6877465777.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=video+enhancer+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_off0000c1cc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1CC 10228 bytes
SHA-256: dfe45d65070d83972890a8af001e5814a3cedfabb48324bdbd82c4250952ff47
font_01_sfnt_off0000d8a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD8A3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f0b5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF0B5 16180 bytes
SHA-256: 4181c9fd5828eab1e7fc740e88e6a7353e9d259bae9e6915237367f5b2c00747