Malicious PDF — malware analysis report

Static analysis result for SHA-256 918bdf8bee8b0fc1…

MALICIOUS

PDF

68.4 KB Created: 2021-10-03 15:09:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 7db5bb682cf92f18d34241a90e0ddd71 SHA-1: 10fb363f8f589642426bf245b56a0ca0ce7361db SHA-256: 918bdf8bee8b0fc11073825a7ec2fd73d20be7ec665aeb20dd33b32678d61431
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript and numerous external links, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent. The embedded JavaScript and link farm structure suggest the PDF is designed to redirect users to malicious sites, likely for phishing or to download further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://chcial.ru/uplcv?utm_term=can+i+remove+a+felony+from+my+record PDF link annotation
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613e855604e8d---vidikaf.pdfIn PDF document text
    • http://evergreendentistryva.com/app/webroot/js/ckfinder/userfiles/files/65201223664.pdfIn PDF document text
    • https://cplastik.com/data/cms/file/jolikepojezufa.pdfIn PDF document text
    • http://penzionnakrizankach.cz/ckfinder/userfiles/files/3368103548.pdfIn PDF document text
    • https://ovistar-dz.com/ckfinder/userfiles/files/17942756782.pdfIn PDF document text
    • https://kompaspt1.com/contents/files/39665242031.pdfIn PDF document text
    • http://abwrosedale.com/uploads/files/jazitiwakefi.pdfIn PDF document text
    • http://sonhanint.com/uploadpic/sun/files/202109081147347453.pdfIn PDF document text
    • https://turystycznapodkowa.pl/userfiles/file/zugozefepomuxisibumab.pdfIn PDF document text
    • http://wakingbeauty.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146a81585794---58222369130.pdfIn PDF document text
    • http://purepassion.pl/userfiles/file/18861476073.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/46837431005.pdfIn PDF document text
    • http://www.mediagrand.hu/data/editorfile/xorikuvimavedifuni.pdfIn PDF document text
    • https://www.tri-or.fr/tri-or/ckfinder/userfilesfiles/zanuvujinozesexejokixu.pdfIn PDF document text
    • http://datacomsystems.cz/userfiles/file/lukuvaribixadavun.pdfIn PDF document text
    • https://matharu.ae/userfiles/file/lekanalabixexavovu.pdfIn PDF document text
    • http://www.srijonihealinghome.com/fckimages/file/givokupetibebub.pdfIn PDF document text
    • https://www.opdrrustukalac.com/wp-content/plugins/formcraft/file-upload/server/content/files/16158c8502679a---57756210743.pdfIn PDF document text
    • http://wine-paraphernalia.com/files/winep/_repo/file/77778236608.pdfIn PDF document text
    • https://drticket.ir/basefile/drtiketcom/files/99126007445.pdfIn PDF document text
    • http://artin-intranet.com/ckupload/files/36385755536.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_off0000af49.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAF49 10584 bytes
SHA-256: 15c499dad6a021bf3b04daf7f2df753fb2c650067d0589c8df8ab1b7a88ada2e
font_01_sfnt_off0000c774.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC774 14600 bytes
SHA-256: a79bc66660d5a6f664506b2ce27de29e3360a9e39e18f4eb498e405bb9720056
font_02_sfnt_off0000ec1e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC1E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1