Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8fae8a99f9ab6cb…

MALICIOUS

PDF

77.7 KB Created: 2021-09-05 23:21:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 5a5722853d7951c510608b930d679b27 SHA-1: 3d96427f6f1b377bacc138833d5c6327b86c6e37 SHA-256: a8fae8a99f9ab6cb4cd184780613b318d5bad906b3d0ed7674b03821c51bb498
164 Risk Score

Malware Insights

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

This PDF file contains embedded JavaScript and a link farm pointing to multiple compromised WordPress sites. These sites host further PDF files, suggesting a multi-stage attack. The ClamAV detection and ML classifier indicate malicious intent, likely for phishing or distributing a second-stage payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9980

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c6bf2a826fe---bumasawubowalob.pdf In PDF document text
    • https://coloreverything.love/wp-content/plugins/super-forms/uploads/php/files/154323b9dd146cf63ed78153b9c6d904/nojuvu.pdfIn PDF document text
    • https://mrdak.cc/uploadfile/files/vubakuzipejazejeliv.pdfIn PDF document text
    • http://www.aadhar-interior.com/userfiles/file/14662048238.pdfIn PDF document text
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/573f4ede404090edabd3337b20011757/69325632043.pdfIn PDF document text
    • http://thunderstar.cn/userfiles/file/20210804023142113037450.pdfIn PDF document text
    • https://upaspor.com/resimler/files/41344138003.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d993b550c17---fuxibelonapebiputirajos.pdfIn PDF document text
    • https://veritiesinstitute.com/wp-content/plugins/super-forms/uploads/php/files/4e686f2587dddb906fe848dea7434416/nesanilalekimazepuxinob.pdfIn PDF document text
    • http://webinaris.eu/ckfinder/userfiles/publics/files/nubazoseneliraputatikatid.pdfIn PDF document text
    • http://ttworld.hu/uploads/content_files/files/9498721747.pdfIn PDF document text
    • http://floridainvestment.cz/files/file/solefikuwu.pdfIn PDF document text
    • http://beetsom.com/PROGRAM_FCKeditor_UserFiles/file/40964983860b8a83007417.pdfIn PDF document text
    • http://tipkeo.com/js/ckfinder/userfiles/files/26695160035.pdfIn PDF document text
    • http://weberstellen.ch/userfiles/file/57084586285.pdfIn PDF document text
    • http://monroehighwildcats.com/clients/40160/File/5105396207.pdfIn PDF document text
    • http://studiopetrilli.it/userfiles/files/kupakin.pdfIn PDF document text
    • http://ddaengshop.com/ckupload/files/semedidewerubifafuz.pdfIn PDF document text
    • http://mywayrtk.info/userfiles/file/zemumidekorezeduteb.pdfIn PDF document text
    • http://www.eventoptik.de/upload/files/retumepopuropunipo.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/a4cea8homlvd1vim59d8cf6vf2/ripej.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/22967123695.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=genworth+mortgage+income+calculation+worksheetPDF 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_off0000cb21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCB21 17060 bytes
SHA-256: 1080bfbb3df1767f1a8012758c8d2e1a41c924bbd35bd2b788a0dd0f5e45e0c0
font_01_sfnt_off0000f75b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF75B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010f72.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F72 10992 bytes
SHA-256: c5bb605ceee639048dcce598e87576cbedfc887b3a75e66a4fb0987154bac6dc