Malicious PDF — malware analysis report

Static analysis result for SHA-256 39e03f825117ceb6…

MALICIOUS

PDF

71.1 KB Created: 2021-09-06 12:37:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: a3d4874b954ba261a17e0f6fb1ba1d00 SHA-1: 0b36cdf419ff87eb1f225c7fbbdf8633c306babe SHA-256: 39e03f825117ceb674edab0bb38cd2172e0c98948ae3aa24dad2f4f8181df697
156 Risk Score

Malware Insights

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

The file was identified as malicious by a machine learning classifier and ClamAV, flagging it as a phishing trojan. Static analysis revealed it functions as a link farm, containing numerous URLs pointing to compromised WordPress upload directories and other disposable hosting. These links are likely intended to lure users into downloading further malicious content or visiting phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

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://irlanc.ru/uplcv?utm_term=constructing+meaning+pdf PDF link annotation
    • http://naplesredeals.com/userfiles/files/jijirozelelisiw.pdfIn PDF document text
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ba4a7846a46---nupapijejuj.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160861d021185c---timosezetawikafal.pdfIn PDF document text
    • http://apsons.eu/files/file/nevelawewesawomepevaga.pdfIn PDF document text
    • http://caacoding.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607a1d7bea6cb---52169013330.pdfIn PDF document text
    • https://www.histoiresdegroupes.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1e37b7d7b1---zusobiretokitosuvivi.pdfIn PDF document text
    • http://pizzeria-millemiglia.de/app/webroot/img/editor/file/4197389888.pdfIn PDF document text
    • https://aulacvn.com/upload/fck/file/71806571801.pdfIn PDF document text
    • https://swimproject.eu/wp-content/plugins/super-forms/uploads/php/files/9ad6b3e60db2bdbd8bd6f769179285a8/58710215273.pdfIn PDF document text
    • http://bud-med.eu/userfiles/file/renexaxumapak.pdfIn PDF document text
    • http://onlytech-tunisie.com/userfiles/file/damevulunilem.pdfIn PDF document text
    • https://aduanaldelvalle.mx/userfiles/file/rizekasedaluz.pdfIn PDF document text
    • https://istanbulbalbir.com/upload/ckfinder/files/69723220757.pdfIn PDF document text
    • https://sevsport.info/wp-content/plugins/super-forms/uploads/php/files/e4d18bf72e77c2ee8b20a0b14ee31dfb/vekuxujimebiri.pdfIn PDF document text
    • https://wecareprogram.org/images/file/7710807890.pdfIn PDF document text
    • http://rauvuonsach.com/images/uploads/files/72504787659.pdfIn PDF document text
    • http://kokocurry.gm/userfiles/file/44041468101.pdfIn PDF document text
    • http://chixue.com/uploadfile/file/20210524191837.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073bec276e29---36241444290.pdfIn 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://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_off0000b66f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB66F 15312 bytes
SHA-256: 1e23d69f62844ee8e2d0b12456f93d84eb47a5cfac8236228504e90f31a43489
font_01_sfnt_off0000dda0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA0 11048 bytes
SHA-256: e7a58760b0969c8cc30b36b12f0f2539e2850097a73b7783795f03d77c3b77f7
font_02_sfnt_off0000f736.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF736 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1