Malicious PDF — malware analysis report

Static analysis result for SHA-256 dc98bf757e4f7ff2…

MALICIOUS

PDF

85.4 KB Created: 2021-06-27 14:34:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f8d13b26ad877f792110040b81babe41 SHA-1: fb195f6ea7cf3889a3ca39c554e98415f96eb18c SHA-256: dc98bf757e4f7ff2b075e5d4a739452721a2aab160e418eed87ec117c8269bc2
156 Risk Score

Malware Insights

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

The PDF contains numerous links 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. No scripts were extracted, but the structure and URLs point to a common pattern of using compromised sites to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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 https://inwebjor.ru/uplcv?utm_term=bams+books+free+download
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608cfff264e40---7894865717.pdf
    • https://playgametoday.ru/wp-content/plugins/super-forms/uploads/php/files/20d2335553fab429b714ff0a7b510def/duduzodepeta.pdf
    • http://marathon-gexin.com/Uploadfiles/files/nekojomod.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/33bd4bcb87decf2b8ea4d757f26c3d2e/15632653438.pdf
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/mqlcpv0rpgg8in7ii69rqrmvh8/japuwag.pdf
    • https://ehblending.com/wp-content/plugins/super-forms/uploads/php/files/280c54f8429127371c544eea63888d66/fezonon.pdf
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/9976e621a49db74157ed74b7d8ed7f05/8597961463.pdf
    • https://suhrsmad.dk/wp-content/plugins/formcraft/file-upload/server/content/files/16079cd89ada70---88754707480.pdf
    • http://jjmcp.jp/userfiles/Image/file/49747232806.pdf
    • https://www.limratechnologies.net/wp-content/plugins/formcraft/file-upload/server/content/files/160bada33b3c8b---xifesijavadeb.pdf
    • http://www.louthadventures.ie/wp-content/plugins/formcraft/file-upload/server/content/files/160844c3dc9c44---87741221279.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a2137c4f981---zizedumomax.pdf
    • https://omomediacion.com/wp-content/plugins/super-forms/uploads/php/files/bc2bf27ec418ed9750418ada8bf9a883/bosinodabewixin.pdf
    • https://sygimportaciones.com/wp-content/plugins/super-forms/uploads/php/files/n2g7ch0fnsbi0ue9l3l9aqserh/22868022008.pdf
    • https://plumcourse.com/wp-content/plugins/super-forms/uploads/php/files/15d940fc7b866ee19a54e7cf4ec90111/3696660148.pdf
    • http://www.nisbd.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b031e84c4c---panatuw.pdf
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/gt8so5tsot4isuqocfis9b9g64/28551454393.pdf
    • http://gabinetortodontyczny.eu/userfiles/file/43974668003.pdf
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160c95d77d1dca---wetotilapate.pdf
    • https://cms.blauraum.com/wp-content/plugins/super-forms/uploads/php/files/bd0233a38e268c5fc52b0dd5ba0a7d5c/rujufidasifatujefop.pdf
    • https://atlanthealth.com/wp-content/plugins/super-forms/uploads/php/files/955a1194bbad8a218666a1d77870a2f6/74357819875.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ebfd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBFD 16792 bytes
font_01_sfnt_off00010414.bin
f130216030e11d9011f7e3ac72399fc1ff58f55beb726b5ab774287fd977d349
pdf-font-stream PDF embedded font (sfnt) at offset 0x10414 10696 bytes
font_02_sfnt_off00011cb3.bin
d86a600be698e20f94306a2a94741e7f98df880e6eec1e8c01f7d43e88c2c82c
pdf-font-stream PDF embedded font (sfnt) at offset 0x11CB3 16848 bytes