Malicious PDF — malware analysis report

Static analysis result for SHA-256 3e55106c321a39c2…

MALICIOUS

PDF

87.1 KB Created: 2021-07-08 06:59:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: c0498c04cbd40c075d4bda9994fe70f7 SHA-1: 87d468fb9ea5d0e52c5ed37270ff6d1c80d41aad SHA-256: 3e55106c321a39c2bf43e30e275a942c4afc74bb2ed5fe8f246ce7a6c9916114
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to other PDF files hosted on various domains, including compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO spam. No scripts were extracted, but the structure suggests a link farm designed to lead users to potentially malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9835

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://www.climatisur.com/ckfinder/userfiles/files/desonenapo.pdf In PDF document text
    • http://zawayakw.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ceccc3ef10---20498256433.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/6559101298.pdfIn PDF document text
    • https://communeouchamps.fr/userfiles/file/55717683822.pdfIn PDF document text
    • https://media-get.com/userfiles/files/peserepowinu.pdfIn PDF document text
    • http://inlikeflintlogistics.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a1fe33a79ab---gufevurigat.pdfIn PDF document text
    • http://treeoflifetolfu.com/clients/0/07/07f122ebb3396bb3f917f2e62af81596/File/jesubulenekefarobaxedo.pdfIn PDF document text
    • http://kripasec.com/userfiles/file/39314935410.pdfIn PDF document text
    • http://tele-video.ru/upload/files/daxixexirusisu.pdfIn PDF document text
    • https://alatheir.com/atheirwsfiles/file/patopobidevi.pdfIn PDF document text
    • http://vladjurnalist.ru/archive/file/xaxirekupi.pdfIn PDF document text
    • http://eco-versute.com/app/webroot/ckfinder/userfiles/files/danabunewujanerijixo.pdfIn PDF document text
    • http://expertsystemgroup.com/file_media/file_image/file/gokudewudosukutoposovu.pdfIn PDF document text
    • http://host.keraladreamhomes.com/~viswabrahmathach/admin/fckeditor/editor/filemanager/connectors/php/userfiles/file/jabefagivafadofos.pdfIn PDF document text
    • http://mouaumfb.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608799e813f87---zulotuxon.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/cc85431fb2bd20f0a69004fa66e6f874/82553728785.pdfIn PDF document text
    • http://www.klpreschool.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608de1b55696f---48390563177.pdfIn PDF document text
    • https://solidpractise.com/files/userfiles/file/dixopufutaxuserakuxogomis.pdfIn PDF document text
    • https://floorco.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/f245f94184e581643127c233a1986c23/97992309369.pdfIn PDF document text
    • http://anhbanglaw.com/userfiles/file/20066684908.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ba5c73dc83c---wumetujoporivebunupodat.pdfIn PDF document text
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/s1svr8odtf9opr4fg6vqrt43bp/wiwifubewagomageges.pdfIn PDF document text
    • http://drthchowdary.net/userfiles/file/mogew.pdfIn PDF document text
    • https://asaptransfers.co.uk/wp-content/plugins/super-forms/uploads/php/files/ofh6ccndo76cq76uii28q677k2/11207501633.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/jfr7ifnk475akdt5234mlbevg6/gaviguvunawaduvozilodex.pdfIn PDF document text
    • https://www.novet.de/wp-content/plugins/formcraft/file-upload/server/content/files/160858c0739f75---83777540280.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/A3Ryygt5BCM/uplcv?utm_term=yoga+with+adriene+day+28PDF 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_off0000f21d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF21D 17140 bytes
SHA-256: b855eb53e7501175d4a260cd78893de477f4e707bf7ebb55cf085cae2da042ce
font_01_sfnt_off00011e50.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11E50 10824 bytes
SHA-256: 2b7d07ce997591e39e37f3fc6870ed6de6417c100cf48ce53e14112b4bae60b0
font_02_sfnt_off0001372c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1372C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1