Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1cc3cc2d720e6ab…

MALICIOUS

PDF

77.8 KB Created: 2021-06-22 19:32:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-23
MD5: 0cb1ff5b5f10bcf57ba657d08da2638d SHA-1: 6695b3e0ef74d41da3a6b7477f65a8420689104d SHA-256: b1cc3cc2d720e6ab4d3125cc727cd197679d0d31e7133c2dce0fb687870ad3dd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous links to external websites, many hosted on compromised WordPress installations, suggesting a link farm designed to redirect users to malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the PDF structure and embedded URLs point towards a social engineering attack.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://irlanc.ru/uplcv?utm_term=class+6+practical+geometry+worksheet PDF link annotation
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/34d4881ee59291fc2b88eaebfd40fa51/renirogopopokeb.pdfIn PDF document text
    • https://echipamente-scule.ro/userfiles/file/mezos.pdfIn PDF document text
    • http://ankaser.com/userfiles/file/28744016024.pdfIn PDF document text
    • https://2greenchicks.com/wp-content/plugins/super-forms/uploads/php/files/7b7d0878600ab4be13d1d7a64319b519/37553058912.pdfIn PDF document text
    • https://www.tessilgiada.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607c3330466b3---lofotosafadon.pdfIn PDF document text
    • https://bokseinstituttet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160b0be7972d1c---pavara.pdfIn PDF document text
    • http://www.nbrownies.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1606fb754582c0---68872584948.pdfIn PDF document text
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b21ff48bcf0---44311773411.pdfIn PDF document text
    • http://erbilsunhotel.com/wp-content/plugins/super-forms/uploads/php/files/doc291bcllkih1asvggfmktp06/98268322722.pdfIn PDF document text
    • http://dabaizhongxue.com/upload_fck/file/2021-6-3/20210603185521501431.pdfIn PDF document text
    • http://georgefamilyreunion.org/clients/86186/File/51341943875.pdfIn PDF document text
    • https://www.emmabowman.com/wp-content/plugins/super-forms/uploads/php/files/50c2653ecc48ea3d90831bcf32708095/24102747466.pdfIn PDF document text
    • https://www.themeshcowork.com/wp-content/plugins/super-forms/uploads/php/files/d580fd40657685ddb39ed4477f49ab62/waduxepatizonazelofivesej.pdfIn PDF document text
    • https://genesisbehaviorcenter.com/wp-content/plugins/super-forms/uploads/php/files/6af3ecc8cd6536a890a40a888559d3aa/tagevowok.pdfIn PDF document text
    • https://www.fecomerciomg.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/16099bd5feb49d---21069705164.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn 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_off0000dae1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDAE1 5664 bytes
SHA-256: 52f5f93f357c94cc92d1702b856b6e9c066571b90969370de8d05a0bbeeea6b0
font_01_sfnt_off0000ee08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE08 11356 bytes
SHA-256: 8ab227d7404caa387f66ca13cf73f8864ac015577f03b90a17353635ff0c69aa
font_02_sfnt_off000114ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x114EF 16072 bytes
SHA-256: 24c5c481937acf4f4841e6563a6d7a18cfdb810806c94b09ac0ff4033348c1e6