Malicious PDF — malware analysis report

Static analysis result for SHA-256 048f57d9a0d2f446…

MALICIOUS

PDF

74.9 KB Created: 2021-09-11 23:15:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: bb7155d77d52b3f12860b3cc1d16f29c SHA-1: c45dd13990fff269ec9667e59e79c332df674ab9 SHA-256: 048f57d9a0d2f446baeb80f659de8bc1f0a8d41c4dd4e4b24d349c4bbb73fcc8
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous links pointing to external domains, many of which are hosted on compromised WordPress sites or disposable hosting, suggesting a link farm or phishing lure. The PDF structure and link farm behavior align with common techniques for distributing malware or redirecting users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.6556

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
  • PDF differential parser failed info PDF_DIFFERENTIAL_PARSE_FAILED
    The cross-check parser (pdfminer.six) failed on this file: PDF differential parser failed: PDFSyntaxError. Static heuristics still ran and any of their findings above are valid; only the differential cross-check signal is missing.
  • 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://ark-mr.com/data/home/qxu2063190031/htdocs/uploadfile/files/98632206043.pdf In PDF document text
    • http://lesmashclub.com/imgUpload/files/45631429945.pdfIn PDF document text
    • http://naturalmis.com/userfiles/file/xelugoselezum.pdfIn PDF document text
    • https://www.toptalentusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137e92f216d3---443504738.pdfIn PDF document text
    • https://xn-----6kcabagcgfjsxjciriy6alkh6a7aqk.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/8e0e5d8721484cb002f56ed9ec93d280/kejuxina.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130c922c0183---88294396195.pdfIn PDF document text
    • https://xn--80aesyq.xn--p1ai/files/file/rodepepofedikix.pdfIn PDF document text
    • http://hamkr.com/userData/board/file/71493618972.pdfIn PDF document text
    • https://itracmediav5.com/ckfinder/userfiles/files/85758322977.pdfIn PDF document text
    • http://novaserv.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613552cfa2b1a---67424147351.pdfIn PDF document text
    • http://bptramptour.pl/files/file/366504311.pdfIn PDF document text
    • http://kiddeefire.com/media/userfiles/files/98363678252.pdfIn PDF document text
    • http://akkoryazilim.com/userfiles/file/pelorozu.pdfIn PDF document text
    • http://nuyewrecruitment.com/wp-content/plugins/super-forms/uploads/php/files/3afd55adf6b959f1c3a6f8317e1da184/30955776719.pdfIn PDF document text
    • http://winkeleninzundert.nl/uploadimages/files/besezesaza.pdfIn PDF document text
    • http://1-champagne.com/blog_images/blog_/file/16671289080.pdfIn PDF document text
    • http://fapannimario.it/userfiles/files/92834088169.pdfIn PDF document text
    • http://kd-council.com/upfile/files/45943640891.pdfIn PDF document text
    • http://himalayakebab.com/shipinc/userfiles/files/28319876117.pdfIn PDF document text
    • https://ever-progress.com/upload/files/75089910999.pdfIn PDF document text
    • http://www.sunarsurdurulebilir.com/wp-content/plugins/super-forms/uploads/php/files/dqvvkgh8j51lkr5smje161m933/manudusofowijiloz.pdfIn PDF document text
    • https://textmakareknutsson.se/upload/image/69122062365.pdfIn PDF document text
    • http://domki-kopalino.pl/pliki/49927868119.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=what+is+accessibility+service+in+androidPDF link annotation
    • 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_off0000cf79.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF79 16916 bytes
SHA-256: da91f1985c7aa7bb2a52aca92f60acbbfd58e0f93a1088b47b68b065fe5ff6c9
font_01_sfnt_off0000fa77.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA77 10780 bytes
SHA-256: 105a05f36f0deb30f3720b7880cbf6fdac96a10fb6477ad58f61af646d303959
font_02_sfnt_off00011347.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11347 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1