Malicious PDF — malware analysis report

Static analysis result for SHA-256 78ca633915c1f498…

MALICIOUS

PDF

100.1 KB Created: 2021-07-07 19:27:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: eae67e79681840cda51aea8f6ebd93ce SHA-1: c1a9168900f49219e73b1d94011c9c1559393de8 SHA-256: 78ca633915c1f4989c5d0aad48bfb27e83325c4db7f1173aef9b62ebb0cbffdb
156 Risk Score

Malware Insights

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

The ML classifier and ClamAV detection strongly indicate maliciousness. The PDF contains numerous links, many pointing to compromised WordPress upload directories, suggesting a phishing or redirection scheme. The presence of a link farm on disposable hosting further supports this malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9936

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://cesishotel.lv/res/wysiwyg/file/65334268913.pdf In PDF document text
    • http://sklepjola.pl/userfiles/file/pafonitosuzisogimexeza.pdfIn PDF document text
    • http://profisystem.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1609c45a061c6f---supekisonuwa.pdfIn PDF document text
    • https://estigotours.com/wp-content/plugins/super-forms/uploads/php/files/f35d6cb69ec838152a21e191a6044635/57466805222.pdfIn PDF document text
    • https://haysalon.com/public_html/userfiles/file/88949971844.pdfIn PDF document text
    • http://interel-rus.ru/test/sites/default/files/file/61988638018.pdfIn PDF document text
    • http://accurateverdicts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b8c945676f2---66521902642.pdfIn PDF document text
    • http://www.onegelha.com/wp-content/plugins/super-forms/uploads/php/files/f17dbebbb4d8ab3241a0241dd9278e68/56220011359.pdfIn PDF document text
    • http://www.megasaludips.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8bcc9918b1---30902287429.pdfIn PDF document text
    • https://rescue.bg/wp-content/plugins/formcraft/file-upload/server/content/files/160c42ba493ed9---babanomorugumarikapif.pdfIn PDF document text
    • http://optimus.org.au/wp-content/plugins/formcraft/file-upload/server/content/files/1609880767b2b6---lizosupex.pdfIn PDF document text
    • http://muszempilla.com/files/file/lisobilaf.pdfIn PDF document text
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160923d49d8f09---63758696159.pdfIn PDF document text
    • http://auksozvynas.lt/userfiles/file/talubinatijuvixexitib.pdfIn PDF document text
    • https://www.msolartop.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160b537d80eee5---foremafaloxegatisope.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/16079cd1b9822f---nazejipipatisu.pdfIn PDF document text
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/160b9c54a2d3a4---dimerokunewab.pdfIn PDF document text
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099e476a95b5---bipinixezufujukave.pdfIn PDF document text
    • http://www.uvhk.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094a1977920c---64252380838.pdfIn PDF document text
    • https://editora-arara-azul.com.br/site/admin/ckfinder/userfiles/files/88878324890.pdfIn PDF document text
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/16073db1342dc1---34233744398.pdfIn PDF document text
    • http://unseretochter.com/images/file/xonulifavativivoxenotan.pdfIn PDF document text
    • https://www.sblending.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160c8e109e9b78---42212895074.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/ngfLrbzwjls/uplcv?utm_term=mechanical+syllabus+for+gatePDF 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_off000121d6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x121D6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000139ed.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x139ED 10960 bytes
SHA-256: 30f41869038c93f6e0a5b7122e203206a6520ceb60314a3d3d6f7853b28058a5
font_02_sfnt_off00015350.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15350 17812 bytes
SHA-256: 41e5119ee09da36d96102c5910e8aadb0bb70e2ff60a1fb475933360c18753da