Malicious PDF — malware analysis report

Static analysis result for SHA-256 86e36761ae614bab…

MALICIOUS

PDF

132.0 KB Created: 2021-09-19 02:35:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 853a1662762a79c5eb8668a1f45c177a SHA-1: a632adf8b990c5f358e2bff2b464a120386aea45 SHA-256: 86e36761ae614bab30b5759834e3d55ece668af49a2f91f10a937078aefd3ca0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as a malicious PDF by ClamAV and an ML classifier. It contains numerous embedded URLs pointing to compromised WordPress sites and disposable hosting, suggesting a link farm designed to redirect users. The presence of these links indicates an attempt to direct users to potentially malicious external content, aligning with phishing or malware distribution tactics.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://laborke.ru/uplcv?utm_term=friends+show+full+episodes PDF link annotation
    • http://fsgpj.com/upfolder/e/files/20210908092228.pdfIn PDF document text
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/161329d7321836---39425411294.pdfIn PDF document text
    • http://marleenjansen.nl/images/uploadfiles/53477929356.pdfIn PDF document text
    • http://stoka-saarlouis.de/userfiles/file/figosinigojukazuta.pdfIn PDF document text
    • http://donkaew-furniture.com/ckfinder/userfiles/files/subejotexufezi.pdfIn PDF document text
    • https://www.mclarenpress.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613253ef03d3a---77215423782.pdfIn PDF document text
    • http://www.deadclan.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16136af6391fe2---69269047742.pdfIn PDF document text
    • http://prabashproperties.com/ckfinder/userfiles/files/zexebofof.pdfIn PDF document text
    • https://xn--80adj7cxa.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/d96b0f1e75b997cdc0470b131b766360/21861251410.pdfIn PDF document text
    • http://linker-apps.com/files/pabusovonuvilirup.pdfIn PDF document text
    • http://visusmarble.com/images_upload/files/63490507946.pdfIn PDF document text
    • http://kbcsisa.com/upload/fckeditor/file/80711798002.pdfIn PDF document text
    • http://imoroz.by/upload/file/lofoladokosuwidavibog.pdfIn PDF document text
    • http://m-camper.ru/ckfinder/userfiles/files/52807857594.pdfIn PDF document text
    • http://2ds-creations.fr/userfiles/file/61612785537.pdfIn PDF document text
    • http://dblbtech.com/userfiles/file/77094287999.pdfIn PDF document text
    • http://canadianrockies.ca/files/file/ramolare.pdfIn PDF document text
    • https://yukkumpulgroup2.com/contents/files/fanogu.pdfIn PDF document text
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614117d65cc19---nunizebuxafusobagufuro.pdfIn PDF document text
    • https://repairbase.net/FCKeditor/editor/filemanager/connectors/php/images/file/73129059535.pdfIn PDF document text
    • http://www.thaiticketmajor.com/static/imgUpload/files/55844132559.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_off0001a311.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1A311 10500 bytes
SHA-256: 2721f073ac4fe0e54dc6a9689839ebd66e3711f3db4bc4579e9c79ca0d279b7b
font_01_sfnt_off0001badb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1BADB 18104 bytes
SHA-256: 1ee747456759510c9bb0f326de7ef1b661c998d3f37b84c26e8fbb275c28590e
font_02_sfnt_off0001ea19.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1EA19 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1