Malicious PDF — malware analysis report

Static analysis result for SHA-256 af732dcd230422bc…

MALICIOUS

PDF

82.1 KB Created: 2021-09-16 22:47:05 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 42e372613b938c786ae51bed4a14eab1 SHA-1: 6fe87db05c8a8c7e17c9e75b5301d2a5a4a5b074 SHA-256: af732dcd230422bc5b61e66aeaf43823e404d1e93433e976d63662a030e488e1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicative of a link farm used for phishing or malware distribution. The ML classifier and ClamAV detection strongly suggest malicious intent. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with malicious document delivery, likely via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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.
  • 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://archism.ru/uplcv?utm_term=android+app+store+password PDF link annotation
    • http://lnhaihui.com/userfiles/file/20210906190110_1840511359.pdfIn PDF document text
    • https://shriramsteels.in/public/ckfinder/userfiles/files/nokikifinepuxidixu.pdfIn PDF document text
    • https://vmkstroi.ru/wp-content/plugins/super-forms/uploads/php/files/906dc4f35a4191efece1b12f92f7c679/judugamotasudovanev.pdfIn PDF document text
    • https://nileagriculturalindustries.com/file/81640692303.pdfIn PDF document text
    • https://www.carlosfunes.es/wp-content/plugins/formcraft/file-upload/server/content/files/16132f354d98a1---86445776699.pdfIn PDF document text
    • http://k12kos.com/ckfinder/userfiles/files/renezuwiret.pdfIn PDF document text
    • https://korovin.org/site/img_ufiles/lubaxaxebetonaja.pdfIn PDF document text
    • http://www.dr.schure.net/ckfinder/userfiles/files/gebewiwovujopuxu.pdfIn PDF document text
    • https://confidence-ist.mktechsol.com/ckfinder/userfiles/files/84383790340.pdfIn PDF document text
    • https://grdr.org/paidel/ckfinder/userfiles/files/telukate.pdfIn PDF document text
    • http://bong-dem-long.org/upload/editor/files/rapigew.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/g19t9fsbd8bgvi60otmamhdl4k/dakuxiw.pdfIn PDF document text
    • https://www.loscam.com/lib_common/ckeditor/ckfinder/userfiles/files/72517140872.pdfIn PDF document text
    • http://robwalker.net/fckupload/file/wivaxigopepetifejavadog.pdfIn PDF document text
    • http://stoka-saarlouis.de/userfiles/file/41430487050.pdfIn PDF document text
    • http://www.amedna.com/userfiles/files/61553587343.pdfIn PDF document text
    • https://ewdel.cz/ckfinder/userfiles/files/kabirivalugos.pdfIn PDF document text
    • http://expnavi.com/sites/all/sites/default/files/file/pufupojaxifedapiz.pdfIn PDF document text
    • https://ruiguoex.com/upfile/files/2021/09/02/wixarubofenix.pdfIn PDF document text
    • https://amadesafar.ir/basefile/amadesafarir/files/nusumopadamasixunife.pdfIn PDF document text
    • http://bellina.pl/userfiles/file/dinapazif.pdfIn PDF document text
    • http://tractortools.cz/ckfinder/userfiles/files/vodorafovapugizuguxute.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_off0000de21.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE21 10408 bytes
SHA-256: 64311b92cb82bee28baddcf707b98bf6ddb9e589570c4176b213b38ce984c0ab
font_01_sfnt_off0000f5e6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5E6 17312 bytes
SHA-256: 27bd8a911fbe8e39d93e6bf200a78bd1642e04a0e527e55a7226854382919bf9
font_02_sfnt_off000122d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x122D3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1