Malicious PDF — malware analysis report

Static analysis result for SHA-256 28eccb81448ee06c…

MALICIOUS

PDF

86.4 KB Created: 2021-08-23 15:07:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-22
MD5: 6bcba881103faa03a5e285bbd4bed0fe SHA-1: 17c31399c3ebb1e77e2d2e682e606c34c537f079 SHA-256: 28eccb81448ee06cbe3341aba9d3ae4fec472e52f5bc29163e76e3fb287eab9d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links to compromised WordPress upload directories, suggesting it is part of a link farm designed to host and distribute malicious files. The presence of a visual download button lure further supports the intent to trick users into downloading malware. ClamAV detection and ML classifier results confirm the malicious nature of the file.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/160aace536e1fd---69153848550.pdf In PDF document text
    • http://wccflooring.com/userfiles/files/60949474649.pdfIn PDF document text
    • http://polskienarty.pl/data/aktualnosci_imgs/file/bunuxeruxaguw.pdfIn PDF document text
    • http://kientrucnhacuagio.com/upload/files/15224079877.pdfIn PDF document text
    • http://triumphtoday.org/wp-content/plugins/formcraft/file-upload/server/content/files/160960dcf1c19c---17819707282.pdfIn PDF document text
    • https://an-professional.ru/img/files/file/11390543929.pdfIn PDF document text
    • https://bookatowncar.com/userfiles/file/52202245615.pdfIn PDF document text
    • http://teplospectr.ru/images/files/48450603336.pdfIn PDF document text
    • https://chamsocmuihong.com/wp-content/plugins/super-forms/uploads/php/files/2c0bt963t1gur2gapsou9r0psj/gabuxudeloru.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/f4b8960e8b284c1ea7a17368b254d957/47102820944.pdfIn PDF document text
    • http://www.iamgoingto1996.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f8e4fc0a46---94395502662.pdfIn PDF document text
    • http://polipack.ru/content/file/safijokiligaziv.pdfIn PDF document text
    • http://lalitas-thaimassage-spa.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609a09fef2bad---38371083445.pdfIn PDF document text
    • http://randalljroutson.com/clients/44711/File/39383783258.pdfIn PDF document text
    • http://instalater-macecek.cz/klienti/devel/sneznerolby.cz/ckfinder/userfiles/files/kapazunakuvasinaxenu.pdfIn PDF document text
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c290dd4a647---jekeji.pdfIn PDF document text
    • https://www.golaw.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ced2f656207---42420029752.pdfIn PDF document text
    • http://alliance-vietnam.com/upload/files/tokojasexofirelasen.pdfIn PDF document text
    • https://couvreur-hautdoubs.fr/internet_new/images_et_fichiers//file/27764056528.pdfIn PDF document text
    • http://mindatpeace.us/uploads/files/fegimuvewukeruxufil.pdfIn PDF document text
    • http://www.holzbau-hoelzl.at/wp-content/plugins/formcraft/file-upload/server/content/files/161054107956e8---10429264410.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/9ea76a55d74af545769726b73a1630d9/51249178423.pdfIn PDF document text
    • https://www.rogierstoel.nl/wp-content/plugins/super-forms/uploads/php/files/786ddi95j2ltjs3bn08q1015p5/lobosaserazutosafog.pdfIn PDF document text
    • http://kirilmazbardak.com/userfiles/file/tovobesuzipajixivinujepu.pdfIn PDF document text
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608b4c08232ee---vijosadiret.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=2019+tamil+new+movies+download+isaiminiPDF 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_off0000ede8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEDE8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000105ff.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105FF 10828 bytes
SHA-256: 8ff1603bc3a5b38f32bbd45b828075f52259abb86ed20164b447c86bde482ffe
font_02_sfnt_off00011f19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F19 16696 bytes
SHA-256: 5a1190e17b5031d700568a25c23b37e722582963e4a6e8b8217a2cdb0d73ef87