Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef8cdcf8de66be95…

MALICIOUS

PDF

92.6 KB Created: 2021-06-29 03:20:06 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: ce69410c3d42537ad6b202c8ae2e830a SHA-1: 420d6f64c3999cab5a0605000e3179007a1c0324 SHA-256: ef8cdcf8de66be9513fac156e5e623d1f1c4e396281a1667b93c708818447d74
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. While no scripts were explicitly extracted, the PDF structure and embedded URIs suggest it's designed to lure users to external malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://crysiq.ru/uplcv?utm_term=quickest+way+to+get+checkmate PDF link annotation
    • http://kindervakantieweekdeurne.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608468a5161c8---84301448699.pdfIn PDF document text
    • https://adasms.fr/userfiles/file/zumikeja.pdfIn PDF document text
    • https://www.tai.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160b7fb8d33351---78238342296.pdfIn PDF document text
    • https://btegypt.comfile/69095298473.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/a021a137337d7576c3ef27b2bd97b668/rewogivefaxoxejez.pdfIn PDF document text
    • http://www.cenlajobinator.com/siteuploads/editorimg/file/defivalalirojiwer.pdfIn PDF document text
    • http://toddfamilyreunion.com/clients/4/48/482e924d5a052aa4a0c13eb8a30e0bc8/File/43914599740.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/em216q93v3in3vt19q387j7si4/87958691678.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/92f96b9509604e97ea1ec59a57f76f2b/fuwinatip.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/96fa30d191e07893a09d263e0da5c558/zuzuvuzifigidakakekibema.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160c2c340a37b0---95164437822.pdfIn PDF document text
    • http://urbancollab.com/userfiles/Proj_Name//files/detopakiradi.pdfIn PDF document text
    • http://longarmquiltacademy.net/fckeditor/userfiles/file/69954115126.pdfIn PDF document text
    • https://dusunceokulu.net/resimler/files/nibiteramuvuxesul.pdfIn PDF document text
    • https://arerp.kr/data/file///73197915216.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/uam5iknsl8r2vmuba81lvtsbbe/takuraxefavegekubog.pdfIn PDF document text
    • http://www.gaviprintpack.com/wp-content/plugins/formcraft/file-upload/server/content/files/16089b624bbd8c---vokebita.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092370b01163---33088172640.pdfIn PDF document text
    • http://df-2.de/images/daten/file/jotoxojegife.pdfIn PDF document text
    • https://theshairpodcast.com/wp-content/plugins/super-forms/uploads/php/files/32b759b1402a1215acda6c7f3faeaa6c/92899926235.pdfIn PDF document text
    • https://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b046950d7cb---fazilukofaloxip.pdfIn PDF document text
    • http://www.viksexteriors.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606eff6ebab00---bipukezutodiwes.pdfIn PDF document text
    • http://inspirationallabels.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c48d034f629---87079184827.pdfIn PDF document text
    • https://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609328f106d93---dibimipemifaxalid.pdfIn PDF document text
    • 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_off000106c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x106C9 16844 bytes
SHA-256: ae7e0c8698bf050a0a3eeea6bc47ce3047e53217dcc1cfc2e9b9bfc33b4b9012
font_01_sfnt_off00013240.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13240 10876 bytes
SHA-256: bf544cfca69ec876f717d55d0148f91d8f45974a19c42870ba2264a1a34ebf1e
font_02_sfnt_off00014baf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14BAF 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1