Malicious PDF — malware analysis report

Static analysis result for SHA-256 bcd1bef3a37facc8…

MALICIOUS

PDF

91.4 KB Created: 2021-08-10 04:14:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 7164648b5a96f3b76a29e34840be3eec SHA-1: 665ef4d6e726d6ebdae5bc9ad045ddbd9ea1ecd1 SHA-256: bcd1bef3a37facc8a60a901eb6d23238bb647fb20fd9de9ddc19a3678d6d8edf
156 Risk Score

Malware Insights

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

This PDF was flagged by multiple heuristics and an ML classifier as malicious, with ClamAV identifying it as a phishing trojan. It contains a link farm pointing to various external PDF files hosted on compromised websites, suggesting an attempt to redirect users to malicious content. The `utm_term` parameter in one of the URLs indicates a potential phishing lure related to educational materials.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9209

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 https://cleaner.pl/userfiles/file/65976692251.pdf In PDF document text
    • http://innotec-industrie.be/userfiles/file/19740972812.pdfIn PDF document text
    • http://la-roofers.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160b16073b9537---62445349160.pdfIn PDF document text
    • https://esteticarcare.com/wp-content/plugins/super-forms/uploads/php/files/877bec6508405ed22e94c59ffe0dbfd5/66062223169.pdfIn PDF document text
    • http://ufnk.fr/app/webroot/files/file/12702899268.pdfIn PDF document text
    • http://afro-safari.com/upload/files/72224021779.pdfIn PDF document text
    • http://kameleonhastanc.hu/files/file/lasilakajet.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/cacf2e24005064fb408df9f6e9e92822/86067010766.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/sjqkd4ouduoksom68ok8c6lt6p/komexopogofoviwuga.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/74a367f96fb1d3cd91700de648052337/95040115005.pdfIn PDF document text
    • http://www.altrus.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16108a03e963d2---jadefovopo.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/160b1b0af4c69c---wupipukow.pdfIn PDF document text
    • http://tamphuhiep.com/Images_upload/files/tudipiselagazowepowe.pdfIn PDF document text
    • http://sklepjola.pl/userfiles/file/17055471161.pdfIn PDF document text
    • http://parmalab.it/userfiles/files/6416919851.pdfIn PDF document text
    • http://xn--h1aaebajlcgx.xn--p1ai/sadm_files/pikevax.pdfIn PDF document text
    • http://galluccifaibano.it/userfiles/file/79159027073.pdfIn PDF document text
    • https://sambelteri.com/contents//files/gifilukodazilogiw.pdfIn PDF document text
    • http://project-lovcen.me/userfiles/file/50573699449.pdfIn PDF document text
    • https://workinhotel.com/upload/fckfile/vorojugufi.pdfIn PDF document text
    • https://carthink.org/wp-content/plugins/formcraft/file-upload/server/content/files/160b31acbaa266---34555555754.pdfIn PDF document text
    • http://vtdsbinhthuan.vn/public/uploads/userfiles/file/53831841624.pdfIn PDF document text
    • https://space1500.com/wp-content/plugins/super-forms/uploads/php/files/40ab48e3fac071a00def289c8ab6b0c1/86348342075.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=teachers+schools+and+society+10th+edition+freePDF 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_off00010ded.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10DED 18076 bytes
SHA-256: a079d09e8bba9a4153088a4f1f9a7811c77f520523465bc5603ddb4d18389705
font_01_sfnt_off00013c50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13C50 10824 bytes
SHA-256: f8af254baefd8028927716bdc0daf7b13745cfd02ded3fca16b69a17051c1d3d
font_02_sfnt_off0001554f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1554F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1