Malicious PDF — malware analysis report

Static analysis result for SHA-256 a65adc883b9fd113…

MALICIOUS

PDF

70.3 KB Created: 2021-09-18 17:48:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 98da22100826dcd7e5c1f1d1ae046a69 SHA-1: 1f3f7c8a73b42c4cf46d4891f2cbc4b5f29f6885 SHA-256: a65adc883b9fd1136290c220c44cb3aa66dfa2bbe3b5c18aed1ac9fa6b0c3b22
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that point to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the URL structure and heuristic firings are sufficient to infer a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://drafthe.ru/uplcv?utm_term=unable+to+open+downloaded+files+on+android PDF link annotation
    • https://coil.hk/upload/files/52567936330.pdfIn PDF document text
    • http://yizhu580.com/ckfinder/userfiles/files/45925524519.pdfIn PDF document text
    • http://jungvassar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/33703764094.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/161317299ddeb0---43096563436.pdfIn PDF document text
    • https://aydin-elektrik.com/resimler/files/morifemupovike.pdfIn PDF document text
    • https://inprovitecuador.com/ckfinder/userfiles/files/wozuvopajijazazugobowa.pdfIn PDF document text
    • http://wmsone.com/eimages/file/8743291375.pdfIn PDF document text
    • http://mocphatreal.com/assets/images/ckfinder/files/1519460232.pdfIn PDF document text
    • http://2018.letnifestiwal.pl/ckfinder/userfiles/files/zokex.pdfIn PDF document text
    • http://severstroysnab.ru/userfiles/file/27257180915.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/55ea9c8de52f49e656f7b5cabd3d68a9/gugexopimoteruvidopi.pdfIn PDF document text
    • https://ozanetiket.com/TasarimAcarnet/serhali/upload/files/dadogilame.pdfIn PDF document text
    • https://jhservice.net/imagenes/galeria/files/19336805637.pdfIn PDF document text
    • https://www.espymetcalf.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613f780f6e67c---sekiwinujerif.pdfIn PDF document text
    • http://laiyi-art.com/userfiles/file/sapozeset.pdfIn PDF document text
    • http://uralcomservis.ru/crn_fls/crn_files/wusaginose.pdfIn PDF document text
    • http://soft-pro.hr/upload/datoteke/sexaxanofedodo.pdfIn PDF document text
    • http://realtor-madrid.com/uploades/fckeditorfile/97655493333.pdfIn PDF document text
    • http://esistore.de/userfiles/file/puvoxozegowefesal.pdfIn PDF document text
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613164ce0ed32---vudulemijodotu.pdfIn PDF document text
    • https://mkontakt.com/dat/file/73235816478.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613be07a1f522---tezedobemilebijidovuvenu.pdfIn PDF document text
    • https://grupo-bahia-real-estate.com/ckfinder/userfiles/files/72523458582.pdfIn PDF document text
    • http://joyear.com/ckfinder/userfiles/files/62042574802.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_off0000b395.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB395 10724 bytes
SHA-256: c013c3cd89accf10dc0a5df043ceff51d63cc71d6d13d55dcab15e20f5aa8629
font_01_sfnt_off0000cc28.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC28 15892 bytes
SHA-256: 5f9be26777c0ed3ca7f0e503f30c5e60acd7cd79de869ea0f2825d4a4224ccf8
font_02_sfnt_off0000f2ea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2EA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1