Malicious PDF — malware analysis report

Static analysis result for SHA-256 4fc8edd0fa2dfa1c…

MALICIOUS

PDF

87.9 KB Created: 2021-08-08 18:59:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: bb77a368cdb11067ae7d409cb02155b4 SHA-1: 3c770bbd55c35b123906986ccf80ae09971c28b6 SHA-256: 4fc8edd0fa2dfa1cdfb647f6c4e960e773f5b4fe128a12520f9ebbef604b20c9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms, suggesting a link farm designed to redirect users to potentially malicious content. The presence of embedded URLs and the PDF structure itself point towards an attempt to exploit user trust, likely for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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 https://artsketch.ru/wp-content/plugins/super-forms/uploads/php/files/da1b1951b08ca4a368107127bd4350db/zazixe.pdf In PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1606c9d710548e---kediwatanusoge.pdfIn PDF document text
    • https://www.andrecampbell.ca/wp-content/plugins/super-forms/uploads/php/files/272e859eb1bdfc9a2a8ac928c71b5d4d/14727465719.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/16081d26315541---41710975547.pdfIn PDF document text
    • https://crownprolaw.com/userfiles/Proj_Name//files/44129502342.pdfIn PDF document text
    • https://dacinsara.ro/fckfiles/file/xitojodo.pdfIn PDF document text
    • http://fbrasil.com/userfiles/file///zapatatofupovanamuku.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/vupaloxaziwagu.pdfIn PDF document text
    • http://flambotour.it/themes/userfiles//files/pigibusage.pdfIn PDF document text
    • http://csc025.com/userfiles/file/20210714130114_na3wj3.pdfIn PDF document text
    • http://jinxinghotel.com/uploads/files/84810874845.pdfIn PDF document text
    • https://dcoderesearch.com/uploads/92680581089.pdfIn PDF document text
    • https://minegociomiweb.com/userfiles/file/bibefoni.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/a4115e9ab3e857996d5ffd01470d7300/41360485921.pdfIn PDF document text
    • https://jkmart.net/FCKFiles/File/mivemifamurabuzegiv.pdfIn PDF document text
    • https://socialacademy.gr/wp-content/plugins/super-forms/uploads/php/files/c93ca44268514ae874d480373bbf8aeb/19381785808.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/qqf5b1qqp3n3ugpghkjrsqipt8/denijaresojutipuruxox.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/92cdaa0d36bfca7d6e21ba75210a2090/jujisotaliredanarunumum.pdfIn PDF document text
    • https://big-cash.de/wp-content/plugins/super-forms/uploads/php/files/9tcsu7n5be9snvddhg1hlp2b66/15051187643.pdfIn PDF document text
    • https://radio-aurea.eu/files/file/fanowusiravepanazin.pdfIn PDF document text
    • http://antichigelsi.it/userfiles/files/dunifapixidijefuxawinab.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/semugisuwumipaf.pdfIn PDF document text
    • http://kaies.cn/upfiles/2107130910061217280phi28.pdfIn PDF document text
    • https://xo-sound.ru/userfiles/file/gijevosovekajevusuparow.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=free+printable+dolch+sight+word+booksPDF 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_off0000f35e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF35E 11088 bytes
SHA-256: 1dafb64d51a35fff7c3eab7aca4ccbfc8bcc8bbd26db24ef42754f8981cfb4fb
font_01_sfnt_off00010cbf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CBF 16992 bytes
SHA-256: 08fe668e78532dc1dc22e4b582c37fdf34e03a1a61ec9db9303abf381cfc8e96
font_02_sfnt_off00013925.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13925 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1