Malicious PDF — malware analysis report

Static analysis result for SHA-256 b8f6f67d4b05f099…

MALICIOUS

PDF

82.8 KB Created: 2021-09-02 23:58:53 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-18
MD5: fd8742646aba7948dba20fa1031fbd7d SHA-1: 42a8dc18944d99754ee0bfaf9692eabdb7a55624 SHA-256: b8f6f67d4b05f09993a371a8d60fc71321830067d7759c77fff17e6f4ee62917
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous URLs, many hosted on compromised CMS uploads, indicating a malicious intent to distribute further content or exploit users. The ClamAV detection and ML classifier strongly suggest malicious activity, likely phishing or malware distribution. No scripts were extracted, and the document body was unreadable, limiting the analysis of specific user-facing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9846

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://10glazsikeyrosa.ru/file/71873909260.pdf In PDF document text
    • https://kmkmekanik.com/upload/ckfinder/files/71864654656.pdfIn PDF document text
    • https://action-roofing.com/wp-content/plugins/super-forms/uploads/php/files/ac0c0c575ec58e174d799e3cac3b8f05/66593258347.pdfIn PDF document text
    • https://rugsinc.in/UserFiles/files/64818306035.pdfIn PDF document text
    • http://www.skk.com.hk/admin/ckfinder/userfiles/files/pemugerinumugojemufutofa.pdfIn PDF document text
    • https://daiichitravel.com/uploads/news_file/nuxuwazozexatuta.pdfIn PDF document text
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e63f1041d74---lepileseke.pdfIn PDF document text
    • https://laatjehuisweerstralen.nl/upload/file/45003363412.pdfIn PDF document text
    • https://strategieb2b.com/userfiles/file/48559526236.pdfIn PDF document text
    • http://yourbuilding.ru/userfiles/files/76868967778.pdfIn PDF document text
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/873017ed6581658b15d0b8272adde788/87782918287.pdfIn PDF document text
    • https://shotclock.ca/wp-content/plugins/super-forms/uploads/php/files/17fe95b39117af5819e9687fd73b5d80/feseloporixosobevibujewir.pdfIn PDF document text
    • https://lajovisena.com/gallery/file/36689378799.pdfIn PDF document text
    • https://equinox-e.com/upload/files/25837574026.pdfIn PDF document text
    • http://www.deco-interieure.com/userfiles/file/68771176462.pdfIn PDF document text
    • http://andrenickels.de/ckfinder/userfiles/files/wagubodopadoberob.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bd66f403a6---netatel.pdfIn PDF document text
    • http://sensor4you.com/fckeditor/editor/filemanager/connectors/php/fckeditor/upload/202109/file/5684597550.pdfIn PDF document text
    • http://startmatbaa.com/userfiles/file/gujijeko.pdfIn PDF document text
    • http://bezpieczna-strefa.pl/wp-content/plugins/super-forms/uploads/php/files/495639151de08ee7dddafcc0e69516c0/nudejuzilidepumuzipejeli.pdfIn PDF document text
    • http://aiskreunion.com/clients/b/b4/b417c2091670ce0b0d78f4b231aea02c/File/pakoremelujodimudoleji.pdfIn PDF document text
    • https://weinquartier.at/wp-content/plugins/super-forms/uploads/php/files/c21c11d17adf4cabb9b0115c42092d2d/82896516776.pdfIn PDF document text
    • http://gingerwooddesign.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aaa70f0cdb8---59817044491.pdfIn PDF document text
    • http://pericosrentcar.com.mx/wp-content/plugins/formcraft/file-upload/server/content/files/160d5b6de722b0---kobosatiwuwogufodumewibil.pdfIn PDF document text
    • http://aucoindeshalles.fr/menu/file/71128296341.pdfIn PDF document text
    • http://www.zopfitravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abe776c7ba1---14125769906.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=rhyming+dictionary+book+pdfPDF 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_off0000dc0e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC0E 18584 bytes
SHA-256: ae8bb2ebc10d5d98f467fa92f9dc854b021d22681c9c314381cf5b4ea0296a7e
font_01_sfnt_off00010c2f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C2F 11112 bytes
SHA-256: 946ed262596c29fcea1b7f97cee0444c941233638812d46c0bfdfffd15921305
font_02_sfnt_off00012585.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12585 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1