Malicious PDF — malware analysis report

Static analysis result for SHA-256 81aa27a5a0050987…

MALICIOUS

PDF

87.0 KB Created: 2021-07-30 17:12:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2026-06-05
MD5: 77afc0b5c43f451bb1b3caa4bc5fa131 SHA-1: 3f29d927fd08aeb5f8bb9ee61198a8793030e016 SHA-256: 81aa27a5a0050987e6d476e4f7a8eb467c62c1fb96f75b87073b07d06480f046
156 Risk Score

Malware Insights

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

This PDF was flagged by ML classifiers and ClamAV as malicious. It contains numerous links pointing to compromised CMS uploads and disposable hosting, suggesting a link farm designed to redirect users to malicious sites. The presence of external URIs and link farms indicates an attempt to lead the user to a compromised or malicious resource, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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://ck-tct.ru/userfiles/file/95175955328.pdf In PDF document text
    • https://jahanchart.ir/data/files/file/zovalirepimoj.pdfIn PDF document text
    • https://www.grecosalesinternational.com/wp-content/plugins/formcraft/file-upload/server/content/files/160761a25c30c7---dofupetarujajifanenawur.pdfIn PDF document text
    • http://grandinhr.eu/images/user/file/85246693925.pdfIn PDF document text
    • http://www.hj-bouwt.be/wp-content/plugins/formcraft/file-upload/server/content/files/1609c8e4b90fdf---wusorodufon.pdfIn PDF document text
    • https://amatnieks.com/pictures/image/51425363153.pdfIn PDF document text
    • http://tcurryproperties.com/konadnew/userfiles/file/robuma.pdfIn PDF document text
    • http://limpiasol.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084846e3cfb0---85297941981.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/160a0e6c7cd91d---lozodadajudok.pdfIn PDF document text
    • http://montaze.org/democms/userfiles/file/ditebesovekubu.pdfIn PDF document text
    • http://alaskacounseling.org/clients/8/87/870ae3779d21e956d596131c1dd113ff/File/89795541047.pdfIn PDF document text
    • https://agermag.ro/mm/file/dofoxoketezetasitej.pdfIn PDF document text
    • http://parejalecaros.com/adjunto/upload/fck/files/66507980061.pdfIn PDF document text
    • http://vytvarnyobchod.cz/UserFiles/File/3398900737.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/cbde90bc4a2bcfd72f79534d6b360c49/83979997565.pdfIn PDF document text
    • http://youngthisyear.com/ckfinder/userfiles/files/73435001230.pdfIn PDF document text
    • http://lisahyatthealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d1bee08cd02---22528792721.pdfIn PDF document text
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/66bf4f104a3df63d596103c3fd4bb1a4/82550972702.pdfIn PDF document text
    • https://earthchartercities.org/wp-content/plugins/formcraft/file-upload/server/content/files/16098e0b78aced---jenofow.pdfIn PDF document text
    • http://www.gainerwindows.ca/wp-content/plugins/super-forms/uploads/php/files/nh7oa49njihrsl32vgdf3jer92/902761682.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160707f420188c---16242858150.pdfIn PDF document text
    • https://mycocoa.org/images/upload/files/66529431615.pdfIn PDF document text
    • https://yuktiedu.com/wp-content/plugins/super-forms/uploads/php/files/ff52f8b41df106bc4f3bda13c902a79a/sogaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=prayers+for+strength+during+deathPDF 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_off0000f17d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF17D 16416 bytes
SHA-256: c29a8aba2f7c242cbca52ee5f2eb7af1e5d0122f37ea9fa5929da2ba453669b1
font_01_sfnt_off00011bf5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BF5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001340c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1340C 10800 bytes
SHA-256: 765fdcfdf892dc544e114408dbfa167f6bba43c059eccf946c5ff9027d4f0257