Malicious PDF — malware analysis report

Static analysis result for SHA-256 e918b811cc62bc9e…

MALICIOUS

PDF

83.6 KB Created: 2021-09-20 08:23:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: f84f15d5c4764be9bb9a867f8f06fda1 SHA-1: 06795483a62ec514f220e9041009aaaf1f9a408a SHA-256: e918b811cc62bc9e3ea8592a852c2c59666fb8b5ede408ccd16640cb417f29b0
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document exhibits characteristics of a link farm, with numerous embedded URLs pointing to potentially compromised or disposable hosting. Heuristic analysis and ML classification strongly indicate malicious intent, with ClamAV identifying it as Pdf.Phishing.Trojan. No scripts were extracted, but the extensive use of external links suggests the primary goal is to redirect users to malicious content, likely for phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

Heuristics 6

  • 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.
  • 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://catamma.ru/uplcv?utm_term=life+is+strange+android+apk+full PDF link annotation
    • https://uleshuzatabc.hu/files/file/81484624049.pdfIn PDF document text
    • http://metalzilemboeventi.com/userfiles/files/78220981851.pdfIn PDF document text
    • https://www.passion-rnd.com/upfile/files/2021/09/17/84154768404.pdfIn PDF document text
    • http://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613f22c2c91a5---xenafib.pdfIn PDF document text
    • http://emilygrilltogo.com/uploads/files/movarofezeg.pdfIn PDF document text
    • http://dongshengcable.com/images/upload/File/81236649373.pdfIn PDF document text
    • http://shyjjc.com/v15/Upload/file/202196025412101.pdfIn PDF document text
    • http://quimicahj.com/admin/userfiles/userfiles/file/kemupebafaxemuk.pdfIn PDF document text
    • http://studiolorenzoni.eu/userfiles/files/5559173814.pdfIn PDF document text
    • http://obras.ru/sites/default/files/uploads/mazijazesefex.pdfIn PDF document text
    • http://saiprogetti.net/userfiles/files/kabolozafivuki.pdfIn PDF document text
    • https://activsport.ro/userfiles/file/81089817151.pdfIn PDF document text
    • http://cerescommoditiesltd.com/Images_upload/files/51408232677.pdfIn PDF document text
    • https://greenbins.ca/ckfinder/userfiles/files/revatoxaveza.pdfIn PDF document text
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/16146e52463983---77373713057.pdfIn PDF document text
    • https://apexforestservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161382d4fbb020---18766026393.pdfIn PDF document text
    • https://losungversorger.com/product/file/4054058002.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613e8825af27d---siragosanejorixugib.pdfIn PDF document text
    • http://gzmzwl.com/Uploadfiles/files/18880277824.pdfIn PDF document text
    • http://lapawan15.com/shop/fck_file/file/xufizinovolaguk.pdfIn PDF document text
    • http://zh-huaxun.com/uploadfiles/files/43927562811.pdfIn PDF document text
    • https://9ja-bet.com/userfiles/file/luzinumaxa.pdfIn PDF document text
    • http://uklearningnetwork.com/userfiles/file/woxewef.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_off0000de12.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE12 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f629.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF629 10824 bytes
SHA-256: 52640b0dc0dfe3c96fb9d83bd4b5e3f2c778bcbc0c399b79c749e7f37817ca94
font_02_sfnt_off00010f0c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10F0C 19096 bytes
SHA-256: 7168d22d8cf3953259242bf0d88345a1c56ed0dd4bf96dd385bf9076b6af3079