Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d8498e2180b2747…

MALICIOUS

PDF

100.0 KB Created: 2021-06-28 04:56:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-15
MD5: 7786748a657407009cb5fc110437a600 SHA-1: a63ef10ad8af3fce0608321e09b725d66a5b7671 SHA-256: 8d8498e2180b274716af5c858cbfeca5f50b0efd90cb7726acb2b003ca116be2
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous external links, many pointing to compromised CMS upload storage and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The document body was unreadable, but the heuristic firings strongly indicate a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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://krassimirtaskov.com/userfiles/files/4543854455.pdf In PDF document text
    • http://www.companyforte.com/imagenes/editor/file/zabirumujoz.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/16083947031b0e---fajadokazuzuxatabakapade.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c166678dd3---88807751489.pdfIn PDF document text
    • http://ruilong-ironwork.com/CKEdit/upload/files/vinuw.pdfIn PDF document text
    • https://famecosmica.it/file/3393000044.pdfIn PDF document text
    • https://hglobaltourb2c.com/FileData/ckfinder/files/20210611_7ED42AF055EAEE6E.pdfIn PDF document text
    • http://sbsinternationalschool.org/sbsisnew/userfiles/file/simoseva.pdfIn PDF document text
    • https://davebakeragency.com/wp-content/plugins/super-forms/uploads/php/files/9faeae4a2311bb42ec14d5c895f1fd46/gedegese.pdfIn PDF document text
    • http://ketoanaca.com/uploads/image/files/15530363637.pdfIn PDF document text
    • https://postscriptproductions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607088fd40ab7---fivorifapiduzojabawep.pdfIn PDF document text
    • http://guides2alpes.fr/uploads/file/26622133196.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/160ab8c3ea4a66---lazuninasunoxar.pdfIn PDF document text
    • http://adamlegal.com/userfiles/file/8479496061.pdfIn PDF document text
    • http://hysansam.com/fckeditor/userfiles/image/68429079437.pdfIn PDF document text
    • http://webursitet.org/Files/file/balakom.pdfIn PDF document text
    • http://recrute.fr/files/files/31534670165.pdfIn PDF document text
    • https://ecef-groupe.com/wp-content/plugins/super-forms/uploads/php/files/kvd8o18qae0qs9ggut58h70hv6/todatolatiro.pdfIn PDF document text
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/gkst9ahvhsqoi7nsjimafq292i/visererapuv.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/16092674507fd8---womesuwexexofepifu.pdfIn PDF document text
    • https://www.davidwoodpersonnel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e3dbb85d1d---34978805796.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfad6fcdab8---92280555716.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=collaboration+example+sentencePDF 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_off000122ad.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122AD 18172 bytes
SHA-256: 9f15672b4f88159304bf3fa423fd65cbf0d82792471fc2c36287915d2f81b0ae
font_01_sfnt_off0001522a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1522A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00016a41.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16A41 10808 bytes
SHA-256: 7572d312e56260909e2f9f5f274e0a3aecc97a65a8d7e02296107c271c0aff24