Malicious PDF — malware analysis report

Static analysis result for SHA-256 b6b5e63a35399436…

MALICIOUS

PDF

73.0 KB Created: 2021-09-26 10:58:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: bb08d294a6537a6440cc5fc5269dc605 SHA-1: 0cebd70c92a4511ad191a04b6013d41b6786b0d9 SHA-256: b6b5e63a353994365ea5a4f8596e1b82460c65a584bd8c38c878d82b6aa77231
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating the presence of JavaScript actions and a link farm pointing to compromised CMS uploads. The embedded JavaScript likely facilitates the redirection to external URLs, such as the one found pointing to a compromised WordPress site, which in turn may serve as a lure for phishing or malware downloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9840

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.
  • JavaScript action low PDF_JAVASCRIPT
    PDF contains a /JavaScript action. 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://krisoc.ru/uplcv?utm_term=among+us+mod+apk+android PDF link annotation
    • http://es-umzuege-transporte.de/wp-content/plugins/super-forms/uploads/php/files/56bfa089250d990fca705fad3b94706c/98830009406.pdfIn PDF document text
    • http://ekogamma.pl/javascript/ckfinder/userfiles/files/wexusexagovixemafujoz.pdfIn PDF document text
    • http://epoptavky.com/is/images/FCKeditor/File/nitajidamebu.pdfIn PDF document text
    • http://ankaraeksioglu.com/resimler/files/7352623409.pdfIn PDF document text
    • https://blokhol.com/upload/files/80877991454.pdfIn PDF document text
    • http://worldofpacifiers.com/editor_uploads/system/files/bakukilemikorogebul.pdfIn PDF document text
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143960d80270---tafezodidul.pdfIn PDF document text
    • https://medsplus.us/admin/images/file/fifuvolafe.pdfIn PDF document text
    • http://dienvietbac.com/uploads/files/popuzovekemajawodatekow.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/np6onmbnt6uqcg4gujfdul1k74/75675911106.pdfIn PDF document text
    • http://xn--80aaaaaikdebj9ccf1ayja1b5a3q.xn--p1ai/ckfinder/userfiles/files/79364263219.pdfIn PDF document text
    • http://www.myhhsi.com/wp-content/plugins/super-forms/uploads/php/files/9506f2766179d563df10ea4cb68f1261/61933462696.pdfIn PDF document text
    • https://flcevent.fcu.edu.tw/plugin/ce1/ckfinder/userfiles/files/20210918161216.pdfIn PDF document text
    • http://ffarchitettura.it/userfiles/files/xurudesufafedaki.pdfIn PDF document text
    • http://sunrui-ti.com/d/files/7156677626.pdfIn PDF document text
    • http://www.ktgroup.co.uk/ckfinder/userfiles/files/91280260154.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1614029518a42a---sanajasawobi.pdfIn PDF document text
    • http://homearcky.nl/userfiles/file/8716175569.pdfIn PDF document text
    • https://shevtsov-art.com/uploads/files/32764902367.pdfIn PDF document text
    • http://topspeed4wd.com/ckfinder/userfiles/files/24106077323.pdfIn PDF document text
    • http://tivati.com/uploads/userfiles/file/12835112109.pdfIn PDF document text
    • https://tongdaidoanhnghiep.com/app/webroot/upload/files/12450886617.pdfIn PDF document text
    • http://appinaris.net/ckfinder/userfiles/publics/files/minafolekawajanaliz.pdfIn PDF document text
    • http://anhuifan.com/upload_fck/file/2021-9-6/20210906002237285319.pdfIn PDF document text
    • http://lempreintedubois.fr/userfiles/lempreintedubois.fr/file/zakoredada.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/66809032598.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_off0000b68c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB68C 10632 bytes
SHA-256: 579f06e8676f46cbfb8cd51002702c3e23c9d8c30d96fe3cfe4130afeef18624
font_01_sfnt_off0000cea5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e6b7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE6B7 18744 bytes
SHA-256: c2bac9b115ab5ed5203fbada4c632ec56a7bad89f86dcaaffc4924a1f5238ea5