Malicious PDF — malware analysis report

Static analysis result for SHA-256 5c57b5df9e772e3b…

MALICIOUS

PDF

79.0 KB Created: 2021-09-01 00:06:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: 141f027fc986cac450c4265c6d067519 SHA-1: 2b254e211a4e3e13d04122924c314d23cd81d1e1 SHA-256: 5c57b5df9e772e3b192cbbb623827451febe8f56bc845bd8fa4c6e5a250a1878
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7972

Heuristics 7

  • 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 to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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://gsnursing.in/ckeditor/ckfinder/userfiles/files/11424445581.pdf In PDF document text
    • http://braciszewska-klimek.pl/fck_files/file/98579128713.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/5d1b98fe2e7249d1e555e69dac3cf379/radalokesivadawilavuvonu.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094d6e8829bc---midilavubumenoje.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/d364ebd5974ba478b8946e6d36c769ca/kifuzej.pdfIn PDF document text
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/6101db243dbdcd6d2c70a809078f7d51/sokavezeserekeneget.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c3c83197eaf---sonin.pdfIn PDF document text
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/tujoxifem.pdfIn PDF document text
    • http://nessium.fr/userfiles/file/33991711826.pdfIn PDF document text
    • https://bestmiamiturf.com/wp-content/plugins/super-forms/uploads/php/files/f826628f5ed2c75a278b05c62561f655/20316177327.pdfIn PDF document text
    • https://amblamy.ee/upload/file/16874876414.pdfIn PDF document text
    • https://norservis.cz/files/files/52758604533.pdfIn PDF document text
    • http://nationalcoopadvisors.com/userfiles/files/removotubik.pdfIn PDF document text
    • http://www.telsercom.com/wp-content/plugins/formcraft/file-upload/server/content/files/161296d479808c---75846518783.pdfIn PDF document text
    • http://studiopignotti.it/userfiles/files/87313193564.pdfIn PDF document text
    • https://gccpay.net/wp-content/plugins/super-forms/uploads/php/files/b824ded77daee0ced4593ee5453b9d2d/85878787069.pdfIn PDF document text
    • https://xn----9sbccjdbca7cyaieg1a3j.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/e543cb0bcb59b7a9c780a51e5fa55b99/48897496271.pdfIn PDF document text
    • https://gikguamerica.com/userfiles/file/64830670387.pdfIn PDF document text
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099a575ca1e0---48402261708.pdfIn PDF document text
    • http://ongnuocdenhat.com/upload/files/fanudemiwuredidonojabez.pdfIn PDF document text
    • https://akemi.ro/hirek/file/vakijizetarud.pdfIn PDF document text
    • http://glina-master.ru/admin/ckfinder/userfiles/files/kufefogi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/FevRqgeaUVY/uplcv?utm_term=chromium+is+used+for+electroplatingPDF 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_off0000ddec.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDEC 11200 bytes
SHA-256: b0776be13282a004dc9a488e8a8d20240f336dfc0f70a11bf35e9763ce75e5c3
font_01_sfnt_off0000f7c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7C7 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010fd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FD9 17468 bytes
SHA-256: 34b8269ef527e353119985121adccc496f9d800f89a651de07ef1ea46bc66437

Open this report in the interactive analyzer, or submit your own file for analysis.