Malicious PDF — malware analysis report

Static analysis result for SHA-256 18b6e89af980cc21…

MALICIOUS

PDF

90.8 KB Created: 2021-10-08 18:55:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 56145c49a5e44c59ed0fb94f093c3c81 SHA-1: 0318a064143b313f26f09b13ce3800f2e135d5a4 SHA-256: 18b6e89af980cc211b5bf4ae550241abc465a19e054ddcd8f5feb0a37551061f
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs that form a link farm, directing users to potentially malicious or compromised websites. Heuristics indicate the PDF is designed to host links on disposable or compromised domains, suggesting a phishing or malware distribution scheme. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

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 https://huntic.ru/uplcv?utm_term=semi+detailed+lesson+plan+for+high+school PDF link annotation
    • https://locoffice.ru/userfiles/file/somazimogezu.pdfIn PDF document text
    • http://dgjst.com/upfile/file/famidusaba.pdfIn PDF document text
    • https://beldaoyun.com/calisma2/files/uploads/28931482877.pdfIn PDF document text
    • https://toscanafantastica.com/userfiles/file/vujozejodakagekipax.pdfIn PDF document text
    • https://global-product.org/CKEdit/upload/files/20046726624.pdfIn PDF document text
    • http://kiiga.ru/userfiles/file/jivurikapetebivi.pdfIn PDF document text
    • https://stijsr.com/userfiles/file/kivefugedezoli.pdfIn PDF document text
    • http://sudeoksa.net/userfiles/file/20210920225012.pdfIn PDF document text
    • http://szentdorottyapatika.hu/files/26773034332.pdfIn PDF document text
    • http://www.perchegouet.com/ckfinder/userfiles/files/10185456734.pdfIn PDF document text
    • http://flapboxes.com/userfiles/files/42691266511.pdfIn PDF document text
    • http://sissonne.hu/editor_up/kilidup.pdfIn PDF document text
    • https://groupburuemas1.com/contents/files/jitadasijiw.pdfIn PDF document text
    • http://xn--aknmedical-yub.com/uploads/file/22958182952.pdfIn PDF document text
    • https://creationstationdance.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614e23b137b66---35275412860.pdfIn PDF document text
    • http://konferencii.org/web/uploads/assets/file/dugirowu.pdfIn PDF document text
    • http://panda-es.tokyo/yamituki-n/uploads/files/20517988216.pdfIn PDF document text
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614ccb4a427ad---tafatakoretedovok.pdfIn PDF document text
    • https://bonekarusa.com/contents/files/19991006488.pdfIn PDF document text
    • http://vntattoosupply.net/uploads/image/files/4789346396.pdfIn PDF document text
    • https://unitytradefze.com/ckfinder/userfiles/files/kifaturawe.pdfIn PDF document text
    • https://starfoil-mail.nl/uploads/wysiwyg/sofivev.pdfIn PDF document text
    • http://szakkepzosiklos.hu/upload/file/lunujixu.pdfIn PDF document text
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/29aeca059bb4b1a382f14b4c44882f26/varefijigini.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_off0000f9f3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF9F3 18784 bytes
SHA-256: 42bd81380cfc380935206532ba7bebd4813783e3e8519ed8ff9973cf841b7c10
font_01_sfnt_off00012b37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B37 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0001434e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1434E 11140 bytes
SHA-256: 694d56bbad961b04eac51caca309892204c8fe43d285b67e35211098d0b30288