Malicious PDF — malware analysis report

Static analysis result for SHA-256 af50842148251f5d…

MALICIOUS

PDF

77.6 KB Created: 2021-09-22 11:55:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 7b93b83a34ed5301299db0b9cfb410ba SHA-1: 1411c17555f38f620076c6bd398170dffda3fa8c SHA-256: af50842148251f5d21d563997a0666269c57ef03834121bdf12902f417280651
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristics indicating it is a link farm, with many URLs pointing to potentially compromised WordPress sites and disposable hosting. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded URLs are indicative of an attempt to redirect users to malicious content, possibly leveraging embedded JavaScript for obfuscation or further redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://medvor.ru/uplcv?utm_term=download+shadow+fight+2+mod+max+level+52 PDF link annotation
    • https://abril.pe/wp-content/plugins/super-forms/uploads/php/files/7n5mtdshbu2vra23c9o6kch0ov/78016949519.pdfIn PDF document text
    • http://tianfonmm.com/d/files/19680117216.pdfIn PDF document text
    • https://keralahappyjourney.com/ckfinder/userfiles/files/pikez.pdfIn PDF document text
    • http://alt-1c.ru/userfiles/file/97545713675.pdfIn PDF document text
    • http://alianzablue.com/aym_image/files/14098038466.pdfIn PDF document text
    • http://cdkuys.handysociality.com/upload/files/69271964492.pdfIn PDF document text
    • http://studioschicchi.eu/userfiles/files/vimuzuxesavijaforetilaru.pdfIn PDF document text
    • http://darec.sk/files/files/nifakiwasuf.pdfIn PDF document text
    • http://autosoftware.company/autoresponders_images/files/zinoto.pdfIn PDF document text
    • http://ylpcl.com/ckfinder/userfiles/files/62350637957.pdfIn PDF document text
    • https://khangle.vn/uploads/images/files/penazikuduguberobaxijo.pdfIn PDF document text
    • https://yennenga.org/business_school/uploads/file/libixikewubilejewef.pdfIn PDF document text
    • http://cukorbetegshop.hu/files/xirojiburazamara.pdfIn PDF document text
    • https://www.educationsexuelle-ecole.ch/ck/ckfinder/userfiles/files/wisuzalolurufuxokavejufol.pdfIn PDF document text
    • http://baanpowertrain.com/wp-content/plugins/formcraft/file-upload/server/content/files/16141f2177e0bf---disorusujebenonunadumaza.pdfIn PDF document text
    • http://ahjygjg.com/upload_fck/file/2021-9-21/20210921235604486431.pdfIn PDF document text
    • https://capitalsyndic.com/userfiles/file/zamozajetibuvuta.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/16140b99e1b567---48116436112.pdfIn PDF document text
    • https://dlt-nkp.com/fileupload/file/kitorexuduripufidoj.pdfIn PDF document text
    • http://status-go.net/gfx/userfiles/files/rapef.pdfIn PDF document text
    • http://bdpq.hungminhits.com/files/uploaded/files/2245347078.pdfIn PDF document text
    • http://kapfenberger-schuetzenverein.at/userfiles/file/xunetoxiroforigadojexu.pdfIn PDF document text
    • https://californiaoptionsrealestate.com/wp-content/plugins/super-forms/uploads/php/files/b73e718a482b55731f4d2fde4591cc19/mopafovawen.pdfIn PDF document text
    • https://spazmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16145d485a0fac---fiwezuw.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_off0000c845.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC845 11208 bytes
SHA-256: cf65386f7b52d5aac83de84723fbd91ae710c7a2d03f105324ec31f043d9db6a
font_01_sfnt_off0000e247.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE247 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000fa59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA59 17932 bytes
SHA-256: a7541aa669a91bd92332749303fc3fe6080ce4ee810aec7c6ab175678b7cc31a