Malicious PDF — malware analysis report

Static analysis result for SHA-256 54836c126b05dc29…

MALICIOUS

PDF

78.1 KB Created: 2021-08-21 10:24:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: e013f6fd112ba851d5fafd8c0b508c7b SHA-1: 8608be4957957f56f3c8ddc661d8ddc013f45df5 SHA-256: 54836c126b05dc29839d2bb8865f4dbf8762fe660d5383da784e22284783a260
156 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 0.8327

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://infrive.ru/uplcv?utm_term=life+is+strange+comic+book+pdf PDF link annotation
    • https://jagominum.com/contents//files/jesolujawa.pdfIn PDF document text
    • http://peoriamayorprayerevent.com/clients/1/16/166e3f524b51ec168ebfd48f86188a1d/File/34998111908.pdfIn PDF document text
    • https://gbeequestriansurfaces.com/wp-content/plugins/super-forms/uploads/php/files/kc3djkgdu8irccar6qlh00j98q/72738136637.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b8718beab33---gamilito.pdfIn PDF document text
    • https://bioesteticaonline.it/file/zidebomelid.pdfIn PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/160872a1d7e742---5505807647.pdfIn PDF document text
    • http://wumag.pl/userfiles/file/bezojaxigu.pdfIn PDF document text
    • http://nail-free.com/ckfinder/userfiles/files/natepinulivoba.pdfIn PDF document text
    • https://ckd-otto.com/contents//files/10442792912.pdfIn PDF document text
    • http://mopi.eu/ckfinder/userfiles/files/lejexefagoseleze.pdfIn PDF document text
    • http://hulstcustoms.ru/uploads/files/5305264255.pdfIn PDF document text
    • http://bascobrunswick.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160e205c8c11c0---71833174339.pdfIn PDF document text
    • http://billedbutikken.dk/articlefiles/file/wodesolebasixubelub.pdfIn PDF document text
    • http://beiwendq.com/userfiles/file/nijap.pdfIn PDF document text
    • https://www.quatainvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607c880a1adc0---23280328818.pdfIn PDF document text
    • https://gotoko.com/cmsv2/upload/files/62938274920.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada1b3c256f---2198931207.pdfIn PDF document text
    • http://terremeraude.com/userfiles/file/1294289937.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/5761c046bbeefedec33e20cb3c8f5a96/dosodagovurelatove.pdfIn PDF document text
    • https://hondaotohaiphong.vn/upload/files/373536792.pdfIn PDF document text
    • http://webelievedin1984.com/clients/6/67/676624d6593aa512bfa6e10e765af00e/File/wajetakovorekagidireku.pdfIn 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_off0000db7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDB7D 11104 bytes
SHA-256: a5de0314e92ca98652a5a2439d2f60491607e98aa90aa9a252185d40cea1dde5
font_01_sfnt_off0000f501.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF501 16796 bytes
SHA-256: 7eb02eb08ff2eb116775a6b8b4b85acacd379a70b3afce2c45762b90597c3179
font_02_sfnt_off000120de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120DE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1