Malicious PDF — malware analysis report

Static analysis result for SHA-256 9b18c1b22161b41d…

MALICIOUS

PDF

84.5 KB Created: 2021-09-07 07:04:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 4f99874b0be9b79adf9a2ad11c3cf271 SHA-1: 299947953d9a5932f4f36531e024464e086a8d55 SHA-256: 9b18c1b22161b41d0335c76787c419a4898f6349f16ed236c8e58a45c407a540
156 Risk Score

Malware Insights

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

The file was detected as malicious by ML classifiers and ClamAV, indicating it is a phishing or trojan PDF. It contains numerous links, many pointing to compromised CMS upload storage or disposable hosting, suggesting a link farm designed to redirect users. The PDF's structure and the presence of external URIs strongly suggest an attempt to exploit users by directing them to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://hc6999.com/userfiles/files/vekowurupivumi.pdf In PDF document text
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/4r0id0smlepbbd1e2h5pkoura4/lonarunigazijezeluw.pdfIn PDF document text
    • http://www.hussco-steel.com/husscofiles/files/verokus.pdfIn PDF document text
    • https://mingyi-lock.com/data/file/userfiles/files/24582041676.pdfIn PDF document text
    • https://controlcert.se/wp-content/plugins/formcraft/file-upload/server/content/files/160df42093f52c---sepanesarudewa.pdfIn PDF document text
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a6ae3c9f335---86524446377.pdfIn PDF document text
    • https://nutrishop.in/ci/userfiles/files/widovukirudufidubenatamo.pdfIn PDF document text
    • https://www.mysmilestudios.com/wp-content/plugins/super-forms/uploads/php/files/b28dfa262541d20cbf68c82e5cf19d72/vuvelawefode.pdfIn PDF document text
    • https://narimasu-chintai.net/jcfiles/file/60949516813.pdfIn PDF document text
    • https://wroclawmodelshow.pl/ckfinder/userfiles/files/20592503513.pdfIn PDF document text
    • https://btegypt.com/file/63004802219.pdfIn PDF document text
    • https://precisionautoandac.com/wp-content/plugins/super-forms/uploads/php/files/ac8b9937599f8a84f4454a432141d01b/25874512612.pdfIn PDF document text
    • http://thehonourride.com/clients/c/c2/c2a221447f3e921143a55eca482c8289/File/71771239358.pdfIn PDF document text
    • https://webmodeli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607585f559886---lufuvujepazir.pdfIn PDF document text
    • http://sangiorgioautoservizi.com/userfiles/files/dopeluvikexamabu.pdfIn PDF document text
    • https://www.nordatec.com/wp-content/plugins/super-forms/uploads/php/files/bn4rfvrnpcrddns8ns4kot9mi1/fukazemetoni.pdfIn PDF document text
    • http://www.melloecastro.com/wp-content/plugins/formcraft/file-upload/server/content/files/16086d47083e2e---15530595306.pdfIn PDF document text
    • http://skrabl.pl/www/rpbd/fck/file/liginoxisobifidemisesunol.pdfIn PDF document text
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/98edcc4a85a1cdad20c51c21e42a0e8e/78666357441.pdfIn PDF document text
    • https://sportli.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160ac5727de96b---42522084298.pdfIn PDF document text
    • https://sskundal.com/userfiles/file/69153746692.pdfIn PDF document text
    • https://www.ideaklinikankara.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607427bb90acf---derugivisulakubujixes.pdfIn PDF document text
    • https://ceilford.org/wp-content/plugins/super-forms/uploads/php/files/3cf7c4a80084f4fa1facb12131e8fdfc/sanipozugilixizeniwawu.pdfIn PDF document text
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/7m5qvib3kvlgshs3hmhv68s38j/visepikigotuv.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=algorithms+for+beginners+pdfPDF 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_off0000e45e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE45E 10904 bytes
SHA-256: 8005bb919a0a9228e30d6897c9d26d7ecda6d52ccc6450497e2881c25853f35a
font_01_sfnt_off0000fcf2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFCF2 18316 bytes
SHA-256: c78711fae923057214d55ce1d0ec2c4cd7f6c1dcc69168803613623a56d57c87
font_02_sfnt_off00012c90.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12C90 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1