Malicious PDF — malware analysis report

Static analysis result for SHA-256 087a778075fa1874…

MALICIOUS

PDF

98.1 KB Created: 2021-07-09 15:43:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: f5726c2537529e5b94579398f97f1611 SHA-1: 20b4bec5ed13867ad49619ac680458fd397c09bc SHA-256: 087a778075fa18747f25d7e680b8bb6ca93536a7a0537877569304ed4f616aaa
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous URLs pointing to domains that appear to be compromised or disposable hosting. The document body is unreadable, but the presence of many external links suggests a phishing or redirection attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9928

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://anonelectronics.com/admin/fckeditor/editor/filemanager/connectors/php/upload_jpg/file/202105010931512614.pdf In PDF document text
    • https://addsfly.com/userfiles/file/rimisesawikapixo.pdfIn PDF document text
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/4tb69hvigckj9966mdlrre4ab7/97673715745.pdfIn PDF document text
    • https://gruntbudowa.pl/files/file/guxisuwenasamotuxede.pdfIn PDF document text
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c001ee55abb---29857280636.pdfIn PDF document text
    • http://bfr-bialapodlaska.pl/userfiles/file/popajimebevefasudepawa.pdfIn PDF document text
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/16076194dbe7f1---kivapufox.pdfIn PDF document text
    • http://admio.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607b950e815e0---93542447264.pdfIn PDF document text
    • http://doktor-okonski.pl/uploadimg/file/majefejis.pdfIn PDF document text
    • https://c4ir.ae/wp-content/plugins/super-forms/uploads/php/files/is2us1uhmdited2s2ar4j77gq7/90269888594.pdfIn PDF document text
    • http://heninrealty.com/userfiles/files/55276711306.pdfIn PDF document text
    • http://hzjksj.com/images/upload/File/17244932832.pdfIn PDF document text
    • http://ridendo.cz/files/file/misumosevedesatobipisuge.pdfIn PDF document text
    • http://xn--80akij1ajew.xn--p1ai/wp-content/plugins/formcraft/file-upload/server/content/files/1608014d35a758---95070575062.pdfIn PDF document text
    • https://harkakotony.hu/UserFiles/file/2890434095.pdfIn PDF document text
    • http://taiyoaquris.cn/upload/userfiles/files/20210705100128.pdfIn PDF document text
    • http://www.restorationservice.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609622d9d01e1---dopajumex.pdfIn PDF document text
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160ab2eef0d919---98171899488.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847866bf79b---49419878606.pdfIn PDF document text
    • http://ngocvietbungalow.com/upload/files/dufidogusuxekiwujifuwafip.pdfIn PDF document text
    • http://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/160ded1e7e68a5---zezofedepesakupaf.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/d6ebe89619a86e5334d276b7ed719431/risofukimi.pdfIn PDF document text
    • https://kfz-gutachter-oliver-schiller.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb40a64a98---salideviki.pdfIn PDF document text
    • http://sivam.pl/files/file/86638615065.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/DOqCt-cVA4I/uplcv?utm_term=reinforced+and+prestressed+concrete+pdfPDF 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_off00011c0b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C0B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001341d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1341D 17720 bytes
SHA-256: 2339735db6d56dcb86ea25983e365311375d81144b952681702a083d15433aeb
font_02_sfnt_off0001628b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1628B 10612 bytes
SHA-256: 66bb6e1a6fef5d7d248e0e68826e8aa13d9dfbe65145b795211fe6fef6e01c96