Malicious PDF — malware analysis report

Static analysis result for SHA-256 8e41a96750ee5db9…

MALICIOUS

PDF

68.7 KB Created: 2021-09-27 10:16:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: de330cdd8be0758a809f9d374924c9bf SHA-1: ee4b4901dd03d93fb3d520839cf71e87539637cf SHA-256: 8e41a96750ee5db91331e405784b859539133000720bce2e2e90b1d6071845d7
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ClamAV as Pdf.Phishing.Trojan and by an ML classifier as malicious. It contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and link farms indicates an attempt to direct users to potentially harmful sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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://synerhu.ru/uplcv?utm_term=kambi+cartoon+pdf+file+download PDF link annotation
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614ce6da62e5a---88512243853.pdfIn PDF document text
    • https://ciar.vn/uploads/image/files/disosabirexijokinonujig.pdfIn PDF document text
    • https://gadd-asso.org/userfiles/file/karimuwifixetawemeder.pdfIn PDF document text
    • http://blackhorsesc.pl/userfiles/file/fipagegurekox.pdfIn PDF document text
    • https://noclegsosnowiec.pl/eurostyl/photos/file/22629216666.pdfIn PDF document text
    • http://stinpo.com/ckfinder/userfiles/files/30204449187.pdfIn PDF document text
    • http://perilatomsk.ru/ckfinder/userfiles/files/5329731461.pdfIn PDF document text
    • http://paillasse.hu/userfiles/file/gakerisajofivivego.pdfIn PDF document text
    • https://distriparkbotlek.nl/userfiles/files/powenazade.pdfIn PDF document text
    • https://clicksnepal.grnca.org/img/files/files/44568535184.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/161484b755332b---26145443445.pdfIn PDF document text
    • http://www.juthamasclinic.com/upload/finder/files/98938264437.pdfIn PDF document text
    • https://dyaa.club/uploads/file/medulobenelivubitoxiti.pdfIn PDF document text
    • http://digitalqwerty.com/ckfinder/userfiles/files/55600977886.pdfIn PDF document text
    • http://bizwd.com/wp-content/plugins/formcraft/file-upload/server/content/files/161306e08986db---dexurosiwulexakapofen.pdfIn PDF document text
    • https://envida-nieuws.nl/bsb_website/upload_fck/file/boweduvovofiperisisemo.pdfIn PDF document text
    • http://driver-jazda.pl/upload/file/28706601596.pdfIn PDF document text
    • http://morecoredesign.com/images/imageUps/files/xokolepi.pdfIn PDF document text
    • http://abnicum.ru/files/file/jaminaduje.pdfIn PDF document text
    • http://mjacz.cz/soubory/files/wafotakifuni.pdfIn PDF document text
    • http://sbstroy53.ru/img/files/17923579813.pdfIn PDF document text
    • https://www.hotel-palladium.gr/wp-content/plugins/super-forms/uploads/php/files/flag4jk42iuvb4glpumkc8ecrn/tuwasaminemedifupojomi.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_off0000ad26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAD26 15532 bytes
SHA-256: 0ff293cd2d1ac32c1bc95d14fc8d648e513d205ad2138ebb458227d4d14726e1
font_01_sfnt_off0000d444.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD444 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000ec5b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC5B 10832 bytes
SHA-256: 3e7975cabbb6554f03411d32b31a2595f1f6acaf64a7ef84b89add4cdd803163