Malicious PDF — malware analysis report

Static analysis result for SHA-256 2111bbb98eaef846…

MALICIOUS

PDF

84.1 KB Created: 2021-09-05 23:33:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 620d29d67a150f03c29d2c85c6fe2be9 SHA-1: 7400463ef91d68f32b30a929fec46952bc55ae37 SHA-256: 2111bbb98eaef846cb391650f27cd9e7fffcb86915e8e7b6fdf9f336ddb04942
156 Risk Score

Malware Insights

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

The PDF contains a link farm directing users to multiple compromised websites, many of which host further PDF files. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The presence of numerous links to compromised CMS upload directories suggests a coordinated effort to host malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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 http://aliguoriarchitetto.eu/userfiles/files/84105208327.pdf In PDF document text
    • http://www.playerclub.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16109b7a83fef1---87113272912.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/bf74672919403c3b1fc7442310a4bcb4/19920589908.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aa2418d5d3d---29337770406.pdfIn PDF document text
    • http://www.primalegal.eu/wp-content/plugins/super-forms/uploads/php/files/35k9ggpj3b0b8qgd9i509oefh7/52961549417.pdfIn PDF document text
    • http://leton.pl/userfiles/file/rawanilavirugujipidu.pdfIn PDF document text
    • https://rfcorporation.net/wp-content/plugins/super-forms/uploads/php/files/8f1bf9371b22e1d7cb1e51f4b2bf1c89/rametejinaxeverapal.pdfIn PDF document text
    • http://konditsionery-odincovo.ru/upload_picture/file/jetosufisol.pdfIn PDF document text
    • http://www.stockholmswingallstars.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f0a374ad03d---11016186274.pdfIn PDF document text
    • https://institut-arabe.org/ckfinder/userfiles/files/27577235082.pdfIn PDF document text
    • https://drmarlenebothma.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16070c896d4c8f---45656055895.pdfIn PDF document text
    • https://mediabandit.com/wp-content/plugins/formcraft/file-upload/server/content/files/16123e431301f8---nedewudoso.pdfIn PDF document text
    • https://myphi.biz/nbloom/fckuploads/file/15541704403.pdfIn PDF document text
    • http://madmojo.com/fckupload/file/dusiwatesitu.pdfIn PDF document text
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/16076b595eabbd---tefelamugosebogositedi.pdfIn PDF document text
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/c4ee1293434b07f39c6a8ece2b2dde06/85408145855.pdfIn PDF document text
    • http://carlaschroyen.com/content_docs/91261998377.pdfIn PDF document text
    • https://xn--hjrnskadeakademien-mtb.se/userfiles/file/getogikifef.pdfIn PDF document text
    • https://numen-wow.com/userfiles/cloud//files/93209594857.pdfIn PDF document text
    • http://divorce-difficile.fr/userfiles/file/36448129115.pdfIn PDF document text
    • https://www.alignerco.ca/wp-content/plugins/super-forms/uploads/php/files/9450bacba50faf0da85f2c4f6a5d1d50/torukizusovap.pdfIn PDF document text
    • http://peter-scherer.de/userfiles/file/33487551564.pdfIn PDF document text
    • https://apparel.allianceflooring.net/wp-content/plugins/super-forms/uploads/php/files/c3822de38be34b2ec8ccdb06c2748c20/pepinudu.pdfIn PDF document text
    • https://muzeumkonstancina.pl/attachments/file/botetujawekuz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=preposition+worksheets+for+third+gradersPDF 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_off0000e448.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE448 10912 bytes
SHA-256: d51ab562b578bc8def885c9cf8c368e4022877154f0064699e69d5c3eefdd23c
font_01_sfnt_off0000fd54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD54 17488 bytes
SHA-256: dd775da29ff1daeab748e21ca386d263da325cb1992f0898e1e3b6a54c15deca
font_02_sfnt_off00012a98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A98 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1