Malicious PDF — malware analysis report

Static analysis result for SHA-256 52d6abc1572d7e19…

MALICIOUS

PDF

85.0 KB Created: 2021-09-20 09:54:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 5557c24836fcd3da5076af8552d6f0b8 SHA-1: 00555764629917aff17dedd533adfd0112933dc5 SHA-256: 52d6abc1572d7e199503b3930a6362cb736f27a9a2931d45d1e8235da2ba3410
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to various websites, many of which appear to be compromised or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of link farming on potentially untrusted domains. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or SEO manipulation.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://crysiq.ru/uplcv?utm_term=best+firestick+streaming
    • http://www.oomewatersport.nl/upload/files/pagiwebatinupuku.pdf
    • http://rpsbchamber.org/editorData/file/41994198788.pdf
    • http://seasonsblinds.com/uploads/ckfinder/userfiles/files/sonatazuwi.pdf
    • http://langeline.com/ckeditor/upload/files/ladedawixupan.pdf
    • http://zzzwchem.com/upload/files/dejobopanim.pdf
    • https://taechoclub.com/FileData/ckfinder/files/20210920_A208D8AFE1C20F93.pdf
    • https://vinaarc.com/app/webroot/files/ckfinder/userfiles/files/gezupobumedufunofove.pdf
    • https://www.stnedu.com/ckfinder/upload/files/22259152219.pdf
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/8c91df6807947ba9cc415b634083c803/nizijonerejixavunufeka.pdf
    • https://aquafilling.com/userfiles/file/39033117600.pdf
    • http://www.truca-taoules.com/ckfinder/userfiles/files/finabojesuj.pdf
    • https://viettrungson.com/media/Files/jitejobazutelazi.pdf
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/16137f53b4ebff---rifaz.pdf
    • http://skipjackpoke.com/ckfinder/userfiles/files/medego.pdf
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/99804409858.pdf
    • https://rallstarawards.us/nbloom/fckuploads/file/kubutekepafudokazipeje.pdf
    • http://mtreurope.com/ckfinder/userfiles/files/mukibigiraxodot.pdf
    • http://www.medicalalliedtraining.com/wp-content/plugins/formcraft/file-upload/server/content/files/16144fa0f5b608---fajezutivuvimen.pdf
    • https://khangle.vn/uploads/images/files/71228506784.pdf
    • https://shop-ecobati.com/medias/upload/files/54499548854.pdf
    • http://circuitoinsulargc.com/documentos/file/nevukanaseduso.pdf
    • http://werder-ritter.de/UserFiles/File/57964846415.pdf
    • https://highlander-inn.com/assets/userfiles/files/19085516154.pdf
    • https://girisimhaber.com/uploads/file/24830337831.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_off0000e7ae.bin
5103222adb55b70b521aef7c5134c441fa50ca0907f4f317a5fd4d9eaa0a211d
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7AE 10656 bytes
font_01_sfnt_off00010020.bin
147c21d386c43be69009eea774158b023b27fa26208ab79c1697efb53616454d
pdf-font-stream PDF embedded font (sfnt) at offset 0x10020 17892 bytes
font_02_sfnt_off00012e61.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12E61 16792 bytes