Malicious PDF — malware analysis report

Static analysis result for SHA-256 fe481a6b6f0e0e84…

MALICIOUS

PDF

84.9 KB Created: 2021-09-02 06:05:25 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: c752ee72eba0ed7ec08945eb2ff2fcd2 SHA-1: 46684fa535ea6f8a5e1dfa10f6009ccb6dc909ef SHA-256: fe481a6b6f0e0e84cc070eaea10490c66a2ff643890e305dd784682ebad4c1a9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. The document body is heavily obfuscated and appears to be metadata from the wkhtmltopdf tool rather than user-readable content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://designklasse.de/ckfinder/userfiles/files/11931827438.pdf In PDF document text
    • http://moonlightmontessori.com/upload/files/fasamurunumevamij.pdfIn PDF document text
    • http://boathousebrokerage.com/userfiles/file/15168339557.pdfIn PDF document text
    • http://dade666.com/userfiles/202108file/2021081911255270554.pdfIn PDF document text
    • http://anapharmata.hu/ckfinder/core/connector/php/files/xijutarofen.pdfIn PDF document text
    • http://art-lan.ru/uploads/assets/file/likapuzapokuvujop.pdfIn PDF document text
    • https://isosklo.cz/uploads/41470497520.pdfIn PDF document text
    • http://aptchasers.com/FCKeditor/userfiles/file/vumupusib.pdfIn PDF document text
    • http://sp2wronki.pl/fotki/fotki/file/vegoxigimusajezog.pdfIn PDF document text
    • https://alihuata.com/userfiles/file/ximamemamatizozudenozomid.pdfIn PDF document text
    • https://vishalahospitality.com/ckfinder/userfiles/files/52611879269.pdfIn PDF document text
    • http://scuderieverdina.it/scuderia/userfiles/file/rakopobimisizoful.pdfIn PDF document text
    • https://nepalmicrofinancesummit.org/userfiles/files/mibijodonemukulafimevi.pdfIn PDF document text
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/68bbcaf286a6ec077edea25e65f4b056/31138481751.pdfIn PDF document text
    • http://westfallassociates.com/documents/file/zifepupezotalugibibofobog.pdfIn PDF document text
    • http://pwr-tech.ru/userfiles/file/28345932449.pdfIn PDF document text
    • http://www.peritaonline.es/ckfinder/userfiles/files/mejuxewozefipevo.pdfIn PDF document text
    • https://limsurdua.com/contents//files/tatidemunizulexaxuguj.pdfIn PDF document text
    • http://marthomaiticherukole.com/userfiles/file/lojatumezotupedenosa.pdfIn PDF document text
    • https://torrentclub.vip/wp-content/plugins/super-forms/uploads/php/files/gag4cmere685192b8e8ipsnous/ziviw.pdfIn PDF document text
    • http://deficanderel.org/clients/6/67/674a09facce11b7629d390eef9534ff9/File/81997862580.pdfIn PDF document text
    • http://phenix-security.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16079564668eaa---xagezesotage.pdfIn PDF document text
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1608fd51cf3d8a---17919725380.pdfIn PDF document text
    • http://thermcom.cz/userfiles/file/kurajatalipumutibemapilur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=fat+but+fitPDF link annotation
    • 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_off0000e852.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE852 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010064.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10064 18896 bytes
SHA-256: 101a69af810562839b23f8f27e1308f8aa8a3d81276dc012f4aa82bfd69ae56c
font_02_sfnt_off00013110.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13110 9752 bytes
SHA-256: b7b1fd89d92349717eb51d24effc3d085fa38cc9bd89d1f47b5a8e7920ea93b6