Malicious PDF — malware analysis report

Static analysis result for SHA-256 19c880e45a2fbd8f…

MALICIOUS

PDF

85.5 KB Created: 2021-06-25 14:41:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 405f23d7d82c155726e64b2317c61348 SHA-1: 5bfbc15101a398b14d91f47b362e2b359689aceb SHA-256: 19c880e45a2fbd8ff88df038d38bcd33cdda60313ab13d65064c4759a2823d30
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier indicating a high probability of malware. The file functions as a link farm, directing users to various compromised websites and potentially malicious PDF files hosted on these sites. The presence of multiple distinct hosts and the use of UTM parameters suggest an attempt to obscure the true destination or to leverage SEO techniques for malicious purposes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • 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://cspdental.com/wp-content/plugins/super-forms/uploads/php/files/741b51c75746642cd5f007df0fd54e07/bidopanerigeb.pdf In PDF document text
    • https://kurek-rowery.pl/user_pict/file/18883348466.pdfIn PDF document text
    • https://www.accidentinjurylascruces.com/wp-content/plugins/super-forms/uploads/php/files/i90jp8980vttdle47c1jrv95pr/76627189076.pdfIn PDF document text
    • http://xn----8sbpvg0afdbe.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/k0d4n7ivqs5unduno74chv7os6/52187530417.pdfIn PDF document text
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c70f2626b70---17628415216.pdfIn PDF document text
    • https://www.higher-energy-trampolineclub.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c6ad534d9fd---34629586190.pdfIn PDF document text
    • https://www.numberoneporthill.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a2c36ea03af---50925438485.pdfIn PDF document text
    • http://aire-limpio.com/img/editor/file/jamuvurelubexoxenonevekop.pdfIn PDF document text
    • https://connect.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/307bcdd63cc9832a5b20a8fb85e9f62c/zaradokurexozerejelejosa.pdfIn PDF document text
    • http://didocrosby.com/imagenes/file/museman.pdfIn PDF document text
    • http://campbellelectronics.com/uploads/namukukodiwafuref.pdfIn PDF document text
    • https://www.abaco-engineering.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a2fa5feba71---79814854528.pdfIn PDF document text
    • https://e-lightingcontrols.com/wp-content/plugins/super-forms/uploads/php/files/abc594ee1e61b137459cd7b47f2ddc3e/vezogegi.pdfIn PDF document text
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609209a818767---vapixezij.pdfIn PDF document text
    • http://pogotowienaukowe.com/Upload/file/solepodifa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=a+doll+house+part+2PDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In 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_off0000ebe3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBE3 17672 bytes
SHA-256: d495b7e754f67d25aff394f6616ff3900650afd75800e9ebe016638b20afb782
font_01_sfnt_off00011975.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11975 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001318c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1318C 10492 bytes
SHA-256: b227dbb03fdf0ae34f3ce70b91339459196c980bd4abaededec66784d135d67b