Malicious PDF — malware analysis report

Static analysis result for SHA-256 66890dbbd5c9e920…

MALICIOUS

PDF

100.2 KB Created: 2021-06-28 01:38:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: b35e71e09dc1beb16f5880d42b3543c2 SHA-1: 1e8067b5d6ddb19586f3e0b4bb4c81198ead373f SHA-256: 66890dbbd5c9e920e8afd59e29cca8b067135dfc6c2c33e359bd0535905122f7
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

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://fitviewer.biz/files/file/64013689590.pdf
    • http://www.stratcareerservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608de77142abb---tebijarawebefozaraxe.pdf
    • https://www.analfissur.com/wp-content/plugins/formcraft/file-upload/server/content/files/160701e1762633---32133650127.pdf
    • https://dm288.rs/slicice/file/sulevefit.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160bf203e97758---25581254138.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/eacq9283ab7o1o5i1lr7vnkl1o/wulerisoxirigokisiminekif.pdf
    • http://stylist.in.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160b414d9cc683---nuvor.pdf
    • http://diysmart.net/userfiles/file/72360261035.pdf
    • http://studiotravenzolo.it/userfiles/files/jisaxefisoxugitelu.pdf
    • https://avistravel.ro/userfiles/file/83538521002.pdf
    • http://www.realisthotel.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073d2769d3af---roroguwesexujijekun.pdf
    • https://tecsal.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608b82271d20f---36975377679.pdf
    • http://photographybynami.com/wp-content/plugins/formcraft/file-upload/server/content/files/16095af024db36---97213948337.pdf
    • http://www.caslyn.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160c6a9d043aaf---delofali.pdf
    • https://comesa.com.pe/wp-content/plugins/super-forms/uploads/php/files/basfcd67vmolak50h4h0em7461/6285685366.pdf
    • https://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/5572536d5ab029b7a6302e7e50516901/buzevuvemoregeliruximisu.pdf
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b9218b1e649---87668690684.pdf
    • http://granitemountainranch.net/userimages/ladaxetakelezikawaka.pdf
    • https://www.euroservicemilano.it/wp-content/plugins/formcraft/file-upload/server/content/files/160b075924255e---27450466978.pdf
    • https://hgb.se/filer/file/mafunujuzokomisumopibome.pdf
    • https://alismobile.co.uk/wp-content/plugins/super-forms/uploads/php/files/2819203eaec455321762551beefe8f5f/51590311136.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=curate+a+collection
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00012632.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12632 16792 bytes
font_01_sfnt_off00013e49.bin
606da34f25cca098ae63909322f199620e41080c7457c5b1323cfbe95e48845b
pdf-font-stream PDF embedded font (sfnt) at offset 0x13E49 10184 bytes
font_02_sfnt_off0001552f.bin
dbc203f2c1178bc3c4a6c0f5ed5022eb0b7f0f016cdba407ba599b7ee399cfec
pdf-font-stream PDF embedded font (sfnt) at offset 0x1552F 17896 bytes