Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf0b104451d3e5c4…

MALICIOUS

PDF

69.1 KB Created: 2021-09-25 08:27:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b6aed2bbee45f280053f14d51bf68bb7 SHA-1: 6a382bcbde9fdfc27eaf7750fe1d0d4c1ba28daf SHA-256: cf0b104451d3e5c47c6a05d65096dad4b657661e12862f82ea515e7b156282f8
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as a phishing lure due to its image-only nature and embedded clickable links. The ML classifier and ClamAV detection strongly indicate malicious intent. The document contains numerous URLs, many pointing to compromised CMS uploads or disposable hosting, suggesting a link farm designed to redirect users to malicious sites, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 1 text block(s), carries a click-outward action, and is only 69 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://ketchas.ru/uplcv?utm_term=how+to+download+real+gta+5+for+android PDF link annotation
    • http://recit-de-vie.fr/userfiles/file/kuvifalopamirodigepirufur.pdfIn PDF document text
    • http://foto-recepty.sk/images/fotky/85353124314.pdfIn PDF document text
    • https://svenjakretschmer.com/ckfinder/userfiles/files/lilurujumetot.pdfIn PDF document text
    • https://laurallo.com/ckfinder/userfiles/files/tobuxikaliraba.pdfIn PDF document text
    • http://www.sparkprototypes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614b7c92785b1---kisif.pdfIn PDF document text
    • http://musicfriend.vn/public/default/ckeditor/files/99130117107.pdfIn PDF document text
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16132535f32d2f---93435811557.pdfIn PDF document text
    • http://avtokit116.ru/!upload/files/butesimonamevir.pdfIn PDF document text
    • http://autoneza.cz/UserFiles/File/lutevosotudasimekinoxuzif.pdfIn PDF document text
    • http://go-pxl.com/uploads/files/gesajasora.pdfIn PDF document text
    • http://medicare-darmstadt.de/bilder/UserImages/file/33917407539.pdfIn PDF document text
    • http://niengrangchuyensau.com/upload/contentFile/file/8005458466.pdfIn PDF document text
    • https://dimensionshoppe.com/alpha/ckfinder/userfiles/files/27002640854.pdfIn PDF document text
    • https://www.simplythebestevents.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161387d0185aaa---karig.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16137eea97136e---beleparosugexagiragi.pdfIn PDF document text
    • https://poolpoint.be/uploads/file/34297461822.pdfIn PDF document text
    • https://g-ortho.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16133161e675eb---86416080866.pdfIn PDF document text
    • https://derya.afmiletisimajansi.info/resimler/files/93119229906.pdfIn PDF document text
    • https://gabconstruction.com/ckfinder/userfiles/files/41510546441.pdfIn PDF document text
    • http://jiachuankeji.com/upload_fck/file/2021-9-25/20210925102802121397.pdfIn PDF document text
    • http://soft-pro.hr/upload/datoteke/60761743113.pdfIn PDF document text
    • http://koppeika.ru/userfiles/file/zarakekusesiguxujisumom.pdfIn PDF document text
    • https://abriganature.centralcms.cloud/galeria/files/tokifigazom.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_off0000b270.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB270 10572 bytes
SHA-256: 29d866a0964f9cdcdc7efbab6ce59d956f6a0942b7dbe2d94d80099373e5ff64
font_01_sfnt_off0000ca81.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA81 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e293.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE293 14420 bytes
SHA-256: f36ae7c3887b14ba3aaec938179d5f163b83af0665f5f4eb45b2e364655f2a44