Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5b8f00b0587181c…

MALICIOUS

PDF

102.6 KB Created: 2021-07-27 02:27:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 00630f50a01a92c67a95cc80a23079cc SHA-1: c360b799a3ff03d85dae361b556242019b00a37b SHA-256: f5b8f00b0587181c132069b24ccef61167b087ede415e46e6050b07a46e6f0f2
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF that contains a link farm pointing to various PDF files hosted on potentially compromised websites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of multiple PDF links on disposable hosting suggests an attempt to obscure the final destination or evade detection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9494

Heuristics 7

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) or Microsoft license-boilerplate documents that carry no urgency or charge/dispute escalation.
  • 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://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/n12m6kun6v89c5j12e48pghqo1/5646027075.pdf In PDF document text
    • http://lohs69.com/clients/82366/File/nonimor.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021052615525973499.pdfIn PDF document text
    • http://www.radanhorse.com/resource/files/zefaxuxaje.pdfIn PDF document text
    • http://tasarimak.net/ckfinder/userfiles/files/71877768269.pdfIn PDF document text
    • http://soundreaming.org/wp-content/plugins/super-forms/uploads/php/files/2e5ed28eab03f095fcd4c041b30e33fa/25458467766.pdfIn PDF document text
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c2b4a3e1cf---midisovada.pdfIn PDF document text
    • https://celebicatering.com/upload/ckfinder/files/berekokegebow.pdfIn PDF document text
    • https://kolodezrus.ru/wp-content/plugins/super-forms/uploads/php/files/b0a8fdefd6335855bee4421d92fa93df/natojekojudazelulurima.pdfIn PDF document text
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/3203a5ec41a98dee528b2bd28cd63788/99819620808.pdfIn PDF document text
    • http://dalnoboy.net/data/filestorage/upload/files/15018147573.pdfIn PDF document text
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/16079bcf00d0c1---18092558822.pdfIn PDF document text
    • http://dalnoboy.net/data/filestorage/upload/files/21821693034.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c1c01a5a658---73650636029.pdfIn PDF document text
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f04a444be5---delenerapufim.pdfIn PDF document text
    • https://aguiapromocional.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160e87ee9491c9---649751075.pdfIn PDF document text
    • https://hashtag.school/userfiles/file/2717049557.pdfIn PDF document text
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160b7a253b268c---tetibujojirufogogarilit.pdfIn PDF document text
    • http://www.misshandicap.ch/wp-content/plugins/formcraft/file-upload/server/content/files/160a36b2c9008f---mexomutub.pdfIn PDF document text
    • http://omniatel.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a0d747ac0fd---3423463034.pdfIn PDF document text
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ec9ae82205c---7933018407.pdfIn PDF document text
    • https://www.cfo-search.com/wp-content/plugins/formcraft/file-upload/server/content/files/160be27d4b8c3c---tetowusefejufag.pdfIn PDF document text
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607e8e6d9f19e---62086382416.pdfIn PDF document text
    • https://biomedchita.ru/imeg_master/file/28022225739.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16093e76709427---10851519727.pdfIn PDF document text
    • http://triple-a.co.th/ckfinder/userfiles/files/masujebopegawoma.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/A3Ryygt5BCM/uplcv?utm_term=examples+of+qualitative+research+topics+in+senior+high+schoolPDF 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0001144d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1144D 16336 bytes
SHA-256: 0ba07f6d54a4cb2ae74247f97c6a926e6d6308299df35fe3bea2e399aa3885da
font_01_sfnt_off00012a82.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A82 17260 bytes
SHA-256: 6fcc1784f4479dee4af7888c71002d0c0d828b00aad9baf5efd9fee98fdcd7af
font_02_sfnt_off000157c4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x157C4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_03_sfnt_off00016fdb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x16FDB 11324 bytes
SHA-256: 1436d492941437fafe42f12e4a2cb7c06639dc975e76500e116f8b18f0e2ac1a