Malicious PDF — malware analysis report

Static analysis result for SHA-256 900fb4cd95ce1bec…

MALICIOUS

PDF

96.6 KB Created: 2021-07-04 08:34:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 033e7923b37df6e996d73195bc858bb3 SHA-1: 98ac8098e8579f0406283bef8dfea587c7ae67c3 SHA-256: 900fb4cd95ce1becfd508e46e70daada4b29496eaae35d4fa0cc01aed23f3ea0
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised WordPress sites or disposable domains, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent, likely to lure users to malicious content via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9929

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://queure.ru/uplcv?utm_term=homophones+meaning+in+english PDF link annotation
    • http://www.mostex.sk/files/articles/file/vores.pdfIn PDF document text
    • http://zhongguohuachun.com/d/files/82121888239.pdfIn PDF document text
    • https://palcev.ru/userfiles/file/44765138911.pdfIn PDF document text
    • https://lightsourceindiana.com/wp-content/plugins/super-forms/uploads/php/files/6fca35fffe260253760d71208e027e4a/kowebugofurunude.pdfIn PDF document text
    • http://www.agenbenangbandung.net/file/webeganololofufumubigi.pdfIn PDF document text
    • http://aryajob.com/user_upload/file/fujuxabeponebitomifavane.pdfIn PDF document text
    • http://sarahscupcakery.com/wp-content/plugins/formcraft/file-upload/server/content/files/16074b4049a097---tapaf.pdfIn PDF document text
    • https://ocvirapuato.com.mx/wp-content/plugins/super-forms/uploads/php/files/cf5a64fe4f14a8a5d4fe64e471ce8aef/gogugezutigulow.pdfIn PDF document text
    • http://exactblue.com/wp-content/plugins/formcraft/file-upload/server/content/files/160961ac73db52---wexukopezapabitubo.pdfIn PDF document text
    • https://puertoestereo.com/wp-content/plugins/super-forms/uploads/php/files/0n9b0njt099ueluc8d6rbgl1j4/90325208777.pdfIn PDF document text
    • http://erex.hu/upload/file/dapilotebazebewola.pdfIn PDF document text
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/f901m4jokfbji7m70ja6hnpj87/62918738021.pdfIn PDF document text
    • http://geombiagioschettino.eu/userfiles/files/ramunugivozabiwufeluzov.pdfIn PDF document text
    • https://stakeoutllc.com/wp-content/plugins/super-forms/uploads/php/files/e8bacd93c138390226b246313a77a498/36246387210.pdfIn PDF document text
    • http://chocolatycakes.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609d6b221862b---64026001364.pdfIn PDF document text
    • http://worthingtonpark101.com/userimages/piviwo.pdfIn PDF document text
    • https://www.kalirich.com/wp-content/plugins/super-forms/uploads/php/files/d7odf41ss4kde543n02pt1ka53/gimol.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fbae2db6e0---28364303998.pdfIn PDF document text
    • http://www.majoriscambio.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a560a403304---dotibokigore.pdfIn PDF document text
    • http://watthaistuttgart.de/userfiles/file/bodevutogamed.pdfIn PDF document text
    • https://jclifeschools.org/wp-content/plugins/super-forms/uploads/php/files/9db3875d33be5610d5b6feb703df242b/46583346649.pdfIn PDF document text
    • https://www.propertyfilevault.com/wp-content/plugins/super-forms/uploads/php/files/907d3aeb26fa7b69d9257c0b538523ea/15857690399.pdfIn PDF document text
    • http://www.sunaryem.com.tr/wp-content/plugins/super-forms/uploads/php/files/tetkb8se8v8hls4j6hkinftg12/buvasovilozis.pdfIn PDF document text
    • http://vipavtoufa.ru/wp-content/plugins/super-forms/uploads/php/files/c5e1a3ee42eb85e3c7fa64dfa4830908/panukiwowopevataxuvilibok.pdfIn PDF document text
    • http://forglass.sk/userfiles/file/76108925242.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_off000118c9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x118C9 17120 bytes
SHA-256: af2d8e2fae51df02aaabb8c8eb0301f5eea45a03c26d3dbbec99198741aa99a3
font_01_sfnt_off00014576.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14576 10492 bytes
SHA-256: fff7aff0e6be7cd99fe4fab4e00e6f7b0ec049b0fb802311868c177246506177
font_02_sfnt_off00015d08.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15D08 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1