Malicious PDF — malware analysis report

Static analysis result for SHA-256 21877a5a33cd69f6…

MALICIOUS

PDF

175.8 KB Created: 2021-06-29 07:23:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: bace11e4a98ca7d7058e1a3ea9af9dba SHA-1: 90ea3493af746112bc034e71a28cde03b04c48c4 SHA-256: 21877a5a33cd69f61b1a5b9f328d436bcf87fe628e618271d6bb75c3fd1f2dd8
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised CMS upload storage or disposable hosting, indicating a link farm. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious document designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9660

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 http://www.verneteco.com/ckfinder/userfiles/files/93426941446.pdf In PDF document text
    • http://serendipityorlando.com/wp-content/plugins/formcraft/file-upload/server/content/files/16085f6fb68e1f---8284754062.pdfIn PDF document text
    • http://baugeraeteverleih.de/benutzerdateien/pukuma.pdfIn PDF document text
    • https://sanidom.pl/img/file/ledepiwezexusitojidi.pdfIn PDF document text
    • http://nicenpos.com/userData/board/file/65798315184.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/16077bf908aa8f---xebixerasujuxelalevowuneb.pdfIn PDF document text
    • https://alcc.vn/wp-content/plugins/super-forms/uploads/php/files/1s5lq5u0aom2flt2mq3reicvmb/xudawunawanatawe.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/1607022ebebaf8---felosukudojurajejeruza.pdfIn PDF document text
    • http://www.cddfct.com/up_files/file/52649032757.pdfIn PDF document text
    • http://www.teeintact.com/admin/fckeditor/editor/filemanager/connectors/php/img/file/xuroz.pdfIn PDF document text
    • http://fine-cottage.ru/userfiles/files/71156850786.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1608bfe6d815ad---91461417054.pdfIn PDF document text
    • http://www.victorian-manor.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16082623635023---54168544850.pdfIn PDF document text
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/160c96c5db0fd8---20686260817.pdfIn PDF document text
    • https://xn----8sbaavnccwq4am.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/ab973346bbce330d2adea978c18e7141/9645751015.pdfIn PDF document text
    • https://g3az.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac8e7f66ac6---42375805099.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/k6mur4ai2f3r7qut6gc1ir7n3r/valalafedu.pdfIn PDF document text
    • https://binarbaid.com/public_html/userfiles/file/87970683372.pdfIn PDF document text
    • http://suacona.com/clients/16856/File/37110745689.pdfIn PDF document text
    • http://www.cheapmotorcycleinsurancepa.com/wp-content/plugins/super-forms/uploads/php/files/r9cnev32m0qo8uti9fc6vsiac6/torinozizuri.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b60259dbd69---kuvevamokaj.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b6a5e5bf61c---19815767876.pdfIn PDF document text
    • http://hgbs.de/userfiles/file/24122963385.pdfIn PDF document text
    • https://stallion-international.com/userfiles/file/vifuwinonop.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c8a0c68b4e---66358709426.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=candy+candy+capitulo+45PDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001b623.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1B623 57004 bytes
SHA-256: 7c1ff68e9256d022443bb50bf5aeef10e71782b6e3b740308040f27be68dde9d
font_01_sfnt_off00024eef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x24EEF 18952 bytes
SHA-256: a8a5d44ce06acc454e60def95367e6f9df78e8444254a18766a940ea2b52bcfc
font_02_sfnt_off00027f4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x27F4D 10564 bytes
SHA-256: 661f729871dbec519c2de5c551325c0567e0a06bd5aa95abd02e6b5bae62b1f7
font_03_sfnt_off0002979a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x2979A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1