Malicious PDF — malware analysis report

Static analysis result for SHA-256 938c8087ee107aa9…

MALICIOUS

PDF

84.8 KB Created: 2021-07-07 20:06:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8b317dee8e4b4d7f90e6b2efd2393b56 SHA-1: 9bc6877143b850150f06e39333c5a067bce03265 SHA-256: 938c8087ee107aa91a3a02d08b2876563c3716f7dc349c7e93cfe2c32c408111
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous links to external websites, many of which are hosted on compromised CMS uploads, indicating a link farm designed to redirect users to malicious content. ClamAV detected this file as 'Pdf.Phishing.Trojan', further supporting its malicious nature. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' suggest an attempt to obscure the final malicious destination through a series of redirects.

Machine Learning

  • Nyx PDF Classifier suspicious score 0.4151

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
  • 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://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607440584ef6a---julabumemub.pdf In PDF document text
    • http://salonlomi.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160a1764ee468f---72807740542.pdfIn PDF document text
    • http://studiosantese.eu/userfiles/files/kotod.pdfIn PDF document text
    • http://huntland.hu/upload/file/japawu.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16087a0ad52e40---pelefagiwupak.pdfIn PDF document text
    • https://cafemocion.com/userfiles/file/mimitavoxoxoluzimezipozok.pdfIn PDF document text
    • http://22743333.com/userfiles/files/41021413017.pdfIn PDF document text
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160afa92354800---77254508549.pdfIn PDF document text
    • http://unnatiwelfareorganization.com/ckfinder/userfiles/files/nabonivizuvazev.pdfIn PDF document text
    • http://ciaooo.ru/uploades/userfiles/file/rutizixokojitosokuj.pdfIn PDF document text
    • http://abnicum.com/files/file/19245945143.pdfIn PDF document text
    • http://magogaralbamoble.com/galeria/files/38412947285.pdfIn PDF document text
    • https://doellefjelde-mussemarked.dk/images/newsmail/file/24201710420.pdfIn PDF document text
    • https://gagiongvitgiong.com/ckfinder/userfiles/files/96930000412.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160806e4d5a22c---89861646638.pdfIn PDF document text
    • http://locthanhwindow.com/img_duhoc/files/tezujuzapiferu.pdfIn PDF document text
    • http://travelport.pl/userfiles//file/13665697437.pdfIn PDF document text
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5b09c62486---11289151588.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9abad3bcc1---816336389.pdfIn PDF document text
    • https://msr-hudsonproperties.com/wp-content/plugins/super-forms/uploads/php/files/dbbb769557e7da43c03e3d4765ebb3f1/sagupumamoter.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160909c0bc39f8---84066000313.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=reference+letter+for+college+scholarshipPDF 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_off0000f441.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF441 16616 bytes
SHA-256: fc6fe985601c7fe6e5b114d100165a966abedd552ee890525eb6e1192d59a141
font_01_sfnt_off00011f6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F6D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013784.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13784 10804 bytes
SHA-256: c12791e7f634aad8825f69d6a7c3e7151479f9897caedc08784c10a499f9a420