Malicious PDF — malware analysis report

Static analysis result for SHA-256 77b84576855384d5…

MALICIOUS

PDF

89.6 KB Created: 2021-07-04 21:17:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: a53f53a4b974ba80f6edb8ee1b930796 SHA-1: 4ad8746312ebb5e0e02d2f8e3fcbde91452aee02 SHA-256: 77b84576855384d5d4969d31772a5aa37093a89f6077d0172c26b5f949e92d7f
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a critical ClamAV detection and an ML classifier. It contains numerous external URLs, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The presence of these links and the overall structure indicate an attempt to lure victims to potentially malicious destinations, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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 https://baconbites.com/wp-content/plugins/super-forms/uploads/php/files/qlbq82rrk7dr0gess2u09n5uf3/jelepaxuvas.pdf In PDF document text
    • http://bakoca.hu/files/file/96023003693.pdfIn PDF document text
    • http://www.korayozelguvenlik.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bbd346e856---jimas.pdfIn PDF document text
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/160de29034c025---42254524143.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/160a227463fc20---49589877634.pdfIn PDF document text
    • https://aftaplan.com/works/peepsparty/html/upload_files/file/94419524223.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e57a0501f8---28738848511.pdfIn PDF document text
    • http://chia4kids.ru/ckfinder/userfiles/files/videkenusujigite.pdfIn PDF document text
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607368b48e212---13234219456.pdfIn PDF document text
    • https://storage-in-motion.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1bcf55b98c---30285741252.pdfIn PDF document text
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/fb34ba5261c79cb70c87f0250d3b66b1/12366160054.pdfIn PDF document text
    • https://event-connections.net/wp-content/plugins/formcraft/file-upload/server/content/files/160814bc108053---wopevufobi.pdfIn PDF document text
    • https://hotelristorantenovecento.it/wp-content/plugins/super-forms/uploads/php/files/50e2768696ab9ad61bc2c53c4956bb24/65607257259.pdfIn PDF document text
    • https://abe-rdc.com/userfiles/file/13575141508.pdfIn PDF document text
    • http://lsbwg.com/ckfinder/userfiles/files/20210628/0617312086.pdfIn PDF document text
    • http://changecn.net/ckupload/files/30603363814.pdfIn PDF document text
    • https://technok.cz/wp-content/plugins/super-forms/uploads/php/files/7883711eac33ade3cb01bb66e9e5fa9c/nuxexukudorufinama.pdfIn PDF document text
    • https://heritagelogs.com/wp-content/plugins/super-forms/uploads/php/files/d2vit6ksfdlcqu18b9cutgk4s4/62806880260.pdfIn PDF document text
    • http://cuatudongbinhduong.net/uploads/files/zevavopotex.pdfIn PDF document text
    • https://www.rockfallco.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d5d89cae26---jedokinalopov.pdfIn PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/18c408f81a6e63139158431320790c8c/90921542334.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/c65d6e1cc45db4cd5a6f8d3533d41023/5066590465.pdfIn PDF document text
    • https://discoverapartmentsforrent.com/wp-content/plugins/super-forms/uploads/php/files/841a8e345de1ff7ac1697cd2c01fe9b2/luxenawarevolasidir.pdfIn PDF document text
    • http://amwordpress.org/wp-content/plugins/formcraft/file-upload/server/content/files/1609c06f9df3d1---71977828680.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=how+to+download+audiomack+on+iphonePDF 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_off0000fabe.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFABE 17372 bytes
SHA-256: 603a7d9d9cdf0a5eb5f7ec4e38e21aded7f1474d48c7d3603f4bf77f0c84b695
font_01_sfnt_off00012861.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12861 10780 bytes
SHA-256: f55aba2b4dd25f91fe6741c84edf89c12c7fd95acb1c6901c1c032326fb102d8
font_02_sfnt_off00014101.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14101 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1