Malicious PDF — malware analysis report

Static analysis result for SHA-256 da797c46b3c6fa61…

MALICIOUS

PDF

73.2 KB Created: 2021-09-25 13:03:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f47661757329d55ed021b5250fd622e6 SHA-1: 0e0a7c1a84ba95f3f2babb8f51d57c12a6c93fe8 SHA-256: da797c46b3c6fa61f5a7b9ea9bdb1d81bc5b04859e2b5276351395c09d322865
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to distribute malicious content. The presence of these URLs and the overall structure indicate a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://allytemp.ru/uplcv?utm_term=android+sdk+vs+android+studio PDF link annotation
    • http://artdental.hu/editor_up/zuzojosupasubox.pdfIn PDF document text
    • https://directorvincentchow.com/fck_filemanager_upload/file/20317274723.pdfIn PDF document text
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/161422f4eb88f2---86471269028.pdfIn PDF document text
    • http://grabnerestriche.at/33102258694.pdfIn PDF document text
    • http://orthodoxvaidikasanghom.org/userfiles/file/pupijum.pdfIn PDF document text
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/1612ea99fb27e7---rojuwuwumukekufevipu.pdfIn PDF document text
    • https://mi-stores.com/basketballtotaal/images/editor/file/40728795438.pdfIn PDF document text
    • http://trans-serwis.com/userfiles/file/606673085.pdfIn PDF document text
    • http://fivelscope.net/fckimages/daxotobi.pdfIn PDF document text
    • http://ck-tct.ru/userfiles/file/86255515659.pdfIn PDF document text
    • http://bndweb.nl/upload/files/jufokejoje.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/5dac582cff23a449bb914c5cf2ff4b77/zaviteteg.pdfIn PDF document text
    • http://pereplanirovkaoblast.ru/pict/file/6168359092.pdfIn PDF document text
    • https://www.tyrtaios.gr/ckfinder/userfiles/files/wogevavesutilaxasukakap.pdfIn PDF document text
    • https://ostrichtours.com/ckfinder/userfiles/files/22750883492.pdfIn PDF document text
    • http://deleeuwputten.nl/site/data/ws/files/4429001852.pdfIn PDF document text
    • https://sentinels.ro/userfiles/file/34990191139.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fe6326cf6a---42561368173.pdfIn PDF document text
    • https://glbtrader.com/userfiles/file/sirasopufinarub.pdfIn PDF document text
    • http://dioceseofniranam.org/userfiles/file/51252392472.pdfIn PDF document text
    • http://janjoling.com/public/ckfinder/userfiles/files/fofivif.pdfIn PDF document text
    • http://hfengly.dk/skoleportalen/userfiles/file/36410871224.pdfIn PDF document text
    • https://consurs.ro/ckfinder/userfiles/files/24178093632.pdfIn PDF document text
    • http://piqiso.ru/userfiles/file/vutagawo.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_off0000b621.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB621 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ce33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCE33 18564 bytes
SHA-256: 50659fd6f1e8ac05980fa8608f7b2f236e97a81aad09abd5eb9d2a6a8bcd448d
font_02_sfnt_off0000fdd9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFDD9 10304 bytes
SHA-256: 52986c198f8056d1f88a6c020d5ba7b467de5ad73c1efc9ee196f6fff544f71f