Malicious PDF — malware analysis report

Static analysis result for SHA-256 4ceb16bc78148131…

MALICIOUS

PDF

85.7 KB Created: 2021-07-05 21:31:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 51c817c3c265da196570571e5b755092 SHA-1: 96a8315e2ada2a2a3076024f4849110f54a222ee SHA-256: 4ceb16bc78148131059f8764323df020b429625a600b9797d94190b678745eac
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, specifically as a phishing trojan. It contains numerous links pointing to compromised WordPress sites, suggesting it's designed to lure users to malicious content. The document body is heavily obfuscated and unreadable, providing no direct clues about its intent beyond the heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/160a68890dd2ea---pijekopuvobi.pdf In PDF document text
    • http://www.adanakursmerkezi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160898e22a7c33---samafara.pdfIn PDF document text
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/16093a83f63baf---54875551687.pdfIn PDF document text
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160c5a37d611e7---3852654081.pdfIn PDF document text
    • https://www.cedicar.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a83436b1177---gefirawepavefadawaleg.pdfIn PDF document text
    • https://wemservice.com/ckfinder/userfiles/files/73146566464.pdfIn PDF document text
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfec8211c19---jolaxufuzetowidijurupafaw.pdfIn PDF document text
    • http://hiddenforrest.net/clients/76790/File/18152400220.pdfIn PDF document text
    • http://younewstoday.com/task/userimages/file/bafezuxugujeremitan.pdfIn PDF document text
    • http://st-communications.com/ckfinder/userfiles/files/6195447365.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb48b8d0b3---nenofelofizemagutaxu.pdfIn PDF document text
    • http://erfolgsapp.de/wp-content/plugins/formcraft/file-upload/server/content/files/16094283bdd700---96805720126.pdfIn PDF document text
    • https://mebelpozakazu.ru/wp-content/plugins/super-forms/uploads/php/files/903c5b03470762d612fbc2bd884fe5ea/10465358297.pdfIn PDF document text
    • https://engineeredrepinc.com/wp-content/plugins/super-forms/uploads/php/files/918c43f10a61069cfe2900e1cff1c76c/50576816003.pdfIn PDF document text
    • https://t2sc.me/userfiles/345619349.pdfIn PDF document text
    • https://www.d-table.com/wp-content/plugins/super-forms/uploads/php/files/2303c791cb99de0d08f16594ae41a061/xejutevitidamesizasemujiz.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/u2t3d2n7ank0j2gvhb3lisjnl1/56557990738.pdfIn PDF document text
    • http://medicare-darmstadt.de/bilder/UserImages/file/verirebilobidaxejegovol.pdfIn PDF document text
    • http://www.kindytennis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a7196729004---zusoxabena.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1608212169eb78---32390709133.pdfIn PDF document text
    • http://yourtruck.be/upload/ckeditor/file/11867220185.pdfIn PDF document text
    • http://vietxetai.com/wp-content/plugins/super-forms/uploads/php/files/i2h141oj6n9ik6iatk9vn56v68/vobiraveladufobu.pdfIn PDF document text
    • https://www.brightfieldbusinesshub.co.uk/wp-content/plugins/super-forms/uploads/php/files/tk2cfe43vg84nffgd1d6m39c80/2791484400.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/zMnd8XtcwSM/uplcv?utm_term=census+in+researchPDF 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_off0000ecfe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECFE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010510.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10510 17600 bytes
SHA-256: 6f3ca999e094796a9704a9fea29d1033e27e607a553156b240dc4d8b6c839274
font_02_sfnt_off00013311.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13311 10196 bytes
SHA-256: ceee86585ddd93db3a73d65315ebbed9befc1dfe3de1e1a06ed7780644133f4c