Malicious PDF — malware analysis report

Static analysis result for SHA-256 278e3ffce6686a9a…

MALICIOUS

PDF

85.0 KB Created: 2021-08-16 02:26:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: ec541c0a9b48fb2bc56f0088c4d918cf SHA-1: 2dd809e443ac28c95975bc11ba268501578d340b SHA-256: 278e3ffce6686a9a9dcf13a3ffdd7a6fd3a9569e3d556974bba812c77b20bf23
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. While no scripts were extracted, the structure and URL patterns are consistent with a malicious PDF dropper.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://www.sacict.or.th/ckfinder/userfiles/files/pageji.pdf In PDF document text
    • https://www.beewellrx.com/wp-content/plugins/super-forms/uploads/php/files/tmp/49030583211.pdfIn PDF document text
    • http://vipdiler.ru/files/file/zugebarajametiburulebo.pdfIn PDF document text
    • https://veaodaibrahma.com/uploads/image/files/puweriwifepavov.pdfIn PDF document text
    • http://cedresarquitectura.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfb1b6704cd---vusuki.pdfIn PDF document text
    • https://parisautotravel.com/wp-content/plugins/super-forms/uploads/php/files/1kk18p2rts92jj1pb1btt8j250/fujawo.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/vinoa05qnr3367m56apulad157/jikililarevez.pdfIn PDF document text
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/1607410d5df702---xazawiwibaguweleda.pdfIn PDF document text
    • http://3e3i.com/UserFiles/file///jekexavovoxeluvevan.pdfIn PDF document text
    • https://www.getfitcrew.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f24348605b---3114278363.pdfIn PDF document text
    • http://garantc.ru/userfiles/file/8842033099.pdfIn PDF document text
    • http://leap-egypt.com/wp-content/plugins/formcraft/file-upload/server/content/files/160cb07784b73f---7161486837.pdfIn PDF document text
    • https://systematix.pl/userfiles/file/porevanumomifojefuv.pdfIn PDF document text
    • http://optikametuje.cz/userfiles/file/12150527466.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160d1e6d497300---68699301160.pdfIn PDF document text
    • http://tsrmmessina.it/userfiles/files/depegowetesata.pdfIn PDF document text
    • http://zabradli-znerezu.cz/userfiles/file/61363619829.pdfIn PDF document text
    • https://stpetejazz.com/wp-content/plugins/super-forms/uploads/php/files/vpisvka685p2qf5soh1hks29kq/juvukerilofibikos.pdfIn PDF document text
    • http://saydersan.com/firma/files/vafegexazolobomawakuzupaj.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/160edf94738eac---5954685419.pdfIn PDF document text
    • https://marbeyoyun.com/calisma2/files/uploads/xeruwokutupu.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/6453353407.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=cursive+writing+a+to+z+capital+letters+pdf+downloadPDF link annotation
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/b7d80eec96aea83227cc341009448050/disivudunavebijagixepena.pdfIn PDF document text
    • 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_off0000e7d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE7D3 11136 bytes
SHA-256: 6aba741fcc5f500989df80ca72710ed067e62e41ae3bb55272056c32613c334e
font_01_sfnt_off000101eb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101EB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000119fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x119FD 17004 bytes
SHA-256: 16cb1b3fa126c0e4c4f1d2bfa1b74bbe2c3d22c8b4f97989f91f24816c45285d