Malicious PDF — malware analysis report

Static analysis result for SHA-256 c83dd12719f94bb2…

MALICIOUS

PDF

75.7 KB Created: 2021-09-20 23:53:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 87b19ecd7f9d7b2af65f1519f29cc637 SHA-1: e08834514a8048cd6bf3ea8b2077a20f6d265575 SHA-256: c83dd12719f94bb299c999f62c3994d8b3bdc71249ba6c7023621359d85dce8f
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised WordPress sites or disposable hosting. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a pattern of creating link farms on potentially untrustworthy domains, suggesting a phishing or malware distribution attempt. The embedded JavaScript likely facilitates the redirection to these malicious URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://irlanc.ru/uplcv?utm_term=hack+pixel+car+racer+apk
    • https://svetplus.com/userfiles/files/25060412155.pdf
    • http://amoy-art.com/Upload/file/35475937446.pdf
    • http://www.bufolari.com/public/immagini/file/86280456719.pdf
    • http://epoch-making.jp/js/upload/files/nujaxozo.pdf
    • http://tehla.eu/userfiles/file/xarejasifosovoxoradoraja.pdf
    • https://giverny-bkk.com/upload/files/vonomazagu.pdf
    • http://xn--o39a91gvwm83kbsn.net/FileData/ckfinder/files/20210902_B1383D486C1B0D0F.pdf
    • http://pileshoppen.dk/userfiles/file/95633345017.pdf
    • https://jdbailbonds.com/wp-content/plugins/super-forms/uploads/php/files/e8de1f81d56f661cac9f52ca6c6d3310/239926689.pdf
    • https://magnanerie-cazilhac.com/userfiles/file/gixilakukugefezetotijiwad.pdf
    • https://ckfinder.pamlskovnik.cz/ckfinder/userfiles/files/21844659670.pdf
    • http://insureavisitor.com/userfiles/file/puxawefinawel.pdf
    • http://lussoleathertiles.com/test4/EDITOR/example/v2/userfiles/file/73410673170.pdf
    • http://adhdesign.de/userContent/files/20210911120643-99856116466.pdf
    • https://peisheng.org/uploads/ckfiles/files/6134fe8a218f7.pdf
    • https://marikakozmetika.hu/editor_up/64639273364.pdf
    • http://www.movingintofreedom.com/wp-content/plugins/formcraft/file-upload/server/content/files/161306b083f8bb---bunutaliri.pdf
    • http://elenasteele.com/wp-content/plugins/formcraft/file-upload/server/content/files/161457f1be7a99---51489294420.pdf
    • http://vongtaygiay.net/media/ftp/file/71022037708.pdf
    • http://uitetenindex.nl/images/uploads/25667174595.pdf
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613e2f1d04d50---65886458399.pdf
    • https://ivfnna.gr/wp-content/plugins/super-forms/uploads/php/files/20726cb595b7d8a8cd69e8c8e46ecfa9/40690854030.pdf
    • https://www.padanguparduotuve.lt/ckfinder/userfiles/files/pesimaxavedajonimi.pdf
    • http://bidwoodmachine.com/d/files/mipimaremeliwus.pdf
    • https://hanoihome.net/img_duhoc/files/tajenepufolakobitulipujaz.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_off0000c5ea.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC5EA 16792 bytes
font_01_sfnt_off0000ddfc.bin
8540fd7396b9ea1968450a694df5c08d0051040f44c2aea7ce64ddf617f5d89f
pdf-font-stream PDF embedded font (sfnt) at offset 0xDDFC 17364 bytes
font_02_sfnt_off00010af8.bin
594f3096dc7c735fc309e9e4c5b87b46273a1fe9fd31d4180e0805e750628835
pdf-font-stream PDF embedded font (sfnt) at offset 0x10AF8 10064 bytes