Malicious PDF — malware analysis report

Static analysis result for SHA-256 186ff32aea20d5f9…

MALICIOUS

PDF

78.1 KB Created: 2021-09-18 16:52:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 12c4c0a3d8b10b065d7561cf709ff933 SHA-1: 620a3d46035ebf33771f00538b69a2ff8412cb5e SHA-256: 186ff32aea20d5f91811566c28ca3dacdbe9fa3f659ef33461fc41de059d5812
162 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is often used to redirect users to malicious websites or download further payloads. Several heuristics indicate the presence of a link farm, with URLs pointing to compromised WordPress sites and disposable hosting, suggesting a phishing or SEO manipulation scheme. The ClamAV detection and ML classifier further support its malicious nature.

Machine Learning

  • Nyx PDF Classifier malicious score 0.7432

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.
  • 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
  • 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://queure.ru/uplcv?utm_term=the+last+day+on+earth+apk+hack PDF link annotation
    • https://hantverksakuten.se/ckfinder/userfiles/files/61702013918.pdfIn PDF document text
    • https://silverbirdmarketing.com/pages/images/file/69692615859.pdfIn PDF document text
    • http://equipociclistaugeraga.com/ciclistas/userfiles/file/14623866478.pdfIn PDF document text
    • http://euhoca.com/js/ckfinder/userfiles/files/58164838502.pdfIn PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/4b704989e5f1717cf08b7b8c7f1e05e3/51567464056.pdfIn PDF document text
    • http://xn--m1age8bh.xn--p1ai/files/file/69742231983.pdfIn PDF document text
    • https://bruceautoservice.com/files/file/nanuxotefisorovepipokik.pdfIn PDF document text
    • https://glasschneider.koeln/wp-content/plugins/super-forms/uploads/php/files/kqmsls0m5h3uos7hj1ursvvl6o/47315651906.pdfIn PDF document text
    • http://sushiyaslo.com/uploads/files/4981549074.pdfIn PDF document text
    • https://kentacademymiango.com/userfiles/file/piveloteremalovagegamop.pdfIn PDF document text
    • http://massiimo.com/piceditor/file/63494987114.pdfIn PDF document text
    • https://salondumariagededijon.com/userfiles/file/46140881555.pdfIn PDF document text
    • http://kystop.com/wp-content/plugins/super-forms/uploads/php/files/01649b52863c3b615d338c94fadb3d8b/dexurumezexasu.pdfIn PDF document text
    • http://mamnonhieutrung.edu.vn/ckfinder/userfiles/files/35741810993.pdfIn PDF document text
    • https://asoriofrio.org/ckfinder/userfiles/files/torineratorivobupazawut.pdfIn PDF document text
    • http://w.scenekunstskolen-efteruddannelsen.dk/ckfinder/userfiles/files/natesibeviriru.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/161438a6610186---84476432315.pdfIn PDF document text
    • http://pegasomeeting.medcoast.net/ckfinder/userfiles/files/44049715306.pdfIn PDF document text
    • http://allseasonsart.com/uploads/fck_uploads/file/49536867688.pdfIn PDF document text
    • http://pepinieres-soupe.com/userfiles/file/17773819529.pdfIn PDF document text
    • http://www.polni.si/Images/files/tesaluf.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/161386b622f44f---kolilarufeb.pdfIn PDF document text
    • http://otevrel.eu/ckfinder/userfiles/files/rafabajazolazelujirobu.pdfIn PDF document text
    • https://skillmapmagazine.com/ckfinder/userfiles/files/60685055238.pdfIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e9b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B9 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000101d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x101D0 10688 bytes
SHA-256: 9a72902ad69d521844cc9950dda166b2de9032c11e6e813f217948e14d2ff94a