Malicious PDF — malware analysis report

Static analysis result for SHA-256 4cebac0c72912685…

MALICIOUS

PDF

81.5 KB Created: 2021-09-18 09:30:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 8887d36c9a30309840b61914c345e9ee SHA-1: 2a56e494b3c1483bf69139012570f10de8cfdd8e SHA-256: 4cebac0c7291268566b2f261d099d89a0d9bcce0632de74f778d2d45cbdbe362
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories, indicating a link farm designed to lure users to external sites. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://quickfix-poland.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145166e3c3ea---7498870006.pdf In PDF document text
    • http://lso-msm.com/userfiles/file/41856223147.pdfIn PDF document text
    • http://larben.cz/media/images/upload/file/78724487180.pdfIn PDF document text
    • http://webinaris.blog/ckfinder/userfiles/publics/files/kogusunexezegozokebif.pdfIn PDF document text
    • https://westhygiene.hu/editor_up/mofatetozofelolomarajuve.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb34f31820---43176271747.pdfIn PDF document text
    • http://neodentpetrosino.it/userfiles/files/kapevajofavev.pdfIn PDF document text
    • https://bselink.com/userfiles/file/29942446210.pdfIn PDF document text
    • http://carrasvilla.es/uploads/files/xofirarular.pdfIn PDF document text
    • http://hart-metale.pl/gimnazjum/userfiles/file/gezobatobibosopizaz.pdfIn PDF document text
    • https://mk-promotions.com/ckfinder/userfiles/files/nodojomolerowon.pdfIn PDF document text
    • http://stressmanagement-karriere.de/userfiles/file/35960757610.pdfIn PDF document text
    • https://xn--80aggmy8c6c.net/UserFiles/File/noxonivinekijat.pdfIn PDF document text
    • http://mail-business.ru/uploads/file/repivoxusatekukorejinizij.pdfIn PDF document text
    • http://gemaeldeundobjekte.de/uploads/files/24034242232.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16139141d7ba87---30385831512.pdfIn PDF document text
    • https://tselectromechanical.com/uploads/CKfiles/files/46568451807.pdfIn PDF document text
    • https://warungmimpishio2.com/contents/files/lezeledetunotitiduk.pdfIn PDF document text
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161315bd119532---84339017864.pdfIn PDF document text
    • http://corising.info/sa_upload/userfiles/file/20210917221017.pdfIn PDF document text
    • http://intelekt.biz/uploads/pages/files/23442475894.pdfIn PDF document text
    • http://skncn.com/u/files/wovabamanakoxotujerul.pdfIn PDF document text
    • http://orthopediedelft.eu/files/kolen.pdfIn PDF document text
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/9f67b59d8e2f66e31d03dc2116428c5a/pamumafakelunidamobifo.pdfIn PDF document text
    • http://888chji.com/userfiles/files/73393522189.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=android+format+usb+drivePDF 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_off0000d765.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD765 18788 bytes
SHA-256: b0e99268c215c40e0b7df14fbc8f7ff859bc7d90ce9f6324a7dc80a4e047d878
font_01_sfnt_off00010800.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10800 10756 bytes
SHA-256: 12a31615e456a978efbb37f32f30fcceb34b942efc5f3cee07fadf6fbb3841f8
font_02_sfnt_off000120c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x120C9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1