Malicious PDF — malware analysis report

Static analysis result for SHA-256 21a402ab45d7d8dc…

MALICIOUS

PDF

82.8 KB Created: 2021-08-23 17:37:08 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 506e517af312d8453e1a0922ec6b0012 SHA-1: 0337d6ad00750b2a3ab3f4ddba02ddccb1b19283 SHA-256: 21a402ab45d7d8dc331dc7be2a9076dbbc20f7f575554d413b9f6f1fdcfb0ec9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised CMS platforms or appear to be part of a link farm designed to manipulate search engine results. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. Although no scripts were explicitly extracted, the PDF structure and embedded links suggest it is designed to redirect users to malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9983

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://www.fliesen-brill.de/wp-content/plugins/formcraft/file-upload/server/content/files/16092316a43478---dinizake.pdf In PDF document text
    • http://jiangsutravel.kr/userfiles/files/20210619_023152.pdfIn PDF document text
    • http://capmar.eu/userfiles/file/10622046056.pdfIn PDF document text
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/9jpl1adqj2seic4m6eq2vhg5j4/mezivizaguwuxe.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bc3ad349c48---ronubolikilap.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bbfacec2d6f---54913989814.pdfIn PDF document text
    • https://narimasu-chintai.net/jcfiles/file/xumuxazigobebusuwopar.pdfIn PDF document text
    • https://www.lamuccacompany.com/wp-content/plugins/super-forms/uploads/php/files/36892326fe0138095af9f4fca7685b30/migurujegusutulu.pdfIn PDF document text
    • http://akinmedikal.com/uploads/file/vogovipepuzabetezotofet.pdfIn PDF document text
    • http://d4smontreal.com/clients/f/f5/f58105ca183540932673f5bf18e62671/File/1839847129.pdfIn PDF document text
    • http://ledson.ru/upload_picture/zateginuputemuja.pdfIn PDF document text
    • https://asiquim.com/ckfinder/userfiles/files/60859090117.pdfIn PDF document text
    • http://ooexperience.be/assets/Image//files/90073177746.pdfIn PDF document text
    • https://www.bocamvigliesrooms.com/wp-content/plugins/super-forms/uploads/php/files/1e8007fd2958220d02257edd9589fbad/zarapibusibikozotorug.pdfIn PDF document text
    • https://kuechentreff-schmid.de/wp-content/plugins/super-forms/uploads/php/files/kuoc503rtor9dkv0n8k5rqa58s/xubekurabepijasaradefewiz.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/160ae22bf959d2---juzadutenifegopakeven.pdfIn PDF document text
    • http://czdashan.cn/uploadfile/file/2021050111331173499.pdfIn PDF document text
    • http://coytex.net//ckfinder/userfiles/files/kewusidenunazeji.pdfIn PDF document text
    • https://rmdschoolandcollege.com/wp-content/plugins/super-forms/uploads/php/files/9h70dtc0q0rm19d4mmjjq2fgi7/35513471833.pdfIn PDF document text
    • http://emanuelarombiarchitetto.eu/userfiles/files/pakaseraka.pdfIn PDF document text
    • https://vickers-electronics.co.uk/wp-content/plugins/super-forms/uploads/php/files/e48ce0cd958b452cf311750cce8f6586/lowaxufafinowo.pdfIn PDF document text
    • https://bostoncake888.com/UserFiles/files/30766831940.pdfIn PDF document text
    • https://hefcom-hydraulics.com/ckfinder/userfiles/files/33779232810.pdfIn PDF document text
    • http://mitsubishilongbien.vn/images/ckeditor/files/82131407752.pdfIn PDF document text
    • http://clarkhigh72.com/clients/3/34/34275c7d49a174b5f6cf03bf5966da6c/File/ruvoxekalabawugufota.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/LPIa9PGmDLg/uplcv?utm_term=fundamentals+of+materials+science+and+engineering+5th+edition+solution+manual+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_off0000de7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE7D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f68f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF68F 16468 bytes
SHA-256: 2d321e9ff9f1a4fbe741c18da57a5288648e09c651bc58bc0f3cb3021a4795f4
font_02_sfnt_off00012173.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12173 11276 bytes
SHA-256: 777e7f44cef66f005b43045e6b6fc05a9c8acccc092136d901fd77ca4959255d