Malicious PDF — malware analysis report

Static analysis result for SHA-256 40555240f648a973…

MALICIOUS

PDF

83.6 KB Created: 2021-09-07 22:24:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 92db2e231137e4dcbb6823ac5802f307 SHA-1: 4f852a8b33491ade90287e2f02b0fd224fb157ce SHA-256: 40555240f648a973b3146740505b898dc8ec2699dc77aa34789498dd78277dfc
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute further malicious content or phish users. The presence of numerous external URIs and the 'PDF_SEO_DISPOSABLE_LINK_FARM' heuristic indicate a deliberate effort to obscure the true malicious destination.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9833

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://www.digitalsofts.com/wp-content/plugins/formcraft/file-upload/server/content/files/160982888ea5ed---56827175128.pdf In PDF document text
    • https://www.syah.org/wp-content/plugins/super-forms/uploads/php/files/ae1aedb6a34f5a565882736a84aebce4/7220755161.pdfIn PDF document text
    • https://www.lindopoint.it/wp-content/plugins/super-forms/uploads/php/files/44e2a6741be565f4f12c2b7e43845256/muzepugolu.pdfIn PDF document text
    • https://grandplaza.bg/uploads/assets/file/nekirun.pdfIn PDF document text
    • http://clearlakesd.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c958637257f---28137619151.pdfIn PDF document text
    • https://transpack-krumbach.de/_upload_bilder/_filemanager/file/80284406811.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/1609b409ae4d7e---gejeko.pdfIn PDF document text
    • https://dentinale.eu/wp-content/plugins/super-forms/uploads/php/files/6af5300b9286dbb59a5c7fcbb5649d47/gawavijejitivi.pdfIn PDF document text
    • http://leguido.net/files/nemeluxunofutaxefumazepav.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/vodomakuwiwokotoj.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/0b074bb0f0d665635b8c989f40a80f9b/12545797135.pdfIn PDF document text
    • http://progettogeometra.it/userfiles/files/sagofebufuvimitenobakavi.pdfIn PDF document text
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/fvn04a1u7324im7uvb6qnv5mt1/83985870698.pdfIn PDF document text
    • http://optikametuje.cz/userfiles/file/mopeporisoguzekupoji.pdfIn PDF document text
    • https://www.edutechusa.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bf15cf58b47---39617094732.pdfIn PDF document text
    • http://grabnerestriche.at/xinopapunutegu.pdfIn PDF document text
    • http://smwiarus.pl/ckfinder/userfiles/files/woluxigokogof.pdfIn PDF document text
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/95740376bd79b61ce7950378607f503d/34809297672.pdfIn PDF document text
    • https://agrachoff.ru/wp-content/plugins/super-forms/uploads/php/files/fe07210e1cd7582b1645286de480cff4/20972401446.pdfIn PDF document text
    • https://www.golddustdental.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132276231a2c---vedibalizuwajaw.pdfIn PDF document text
    • http://cy2hand.com/userfiles/niverinalozasiberofozu.pdfIn PDF document text
    • https://wcfkenzi.com/ckfinder/userfiles/files/rafisavipebawo.pdfIn PDF document text
    • http://nhs1968.com/clients/65482/File/maluvilewesofofilakonixi.pdfIn PDF document text
    • http://www.cddfct.com/up_files/file/75096522945.pdfIn PDF document text
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/tfhns62una4e672c9jaimdsm52/falelovulibikidiwoxi.pdfIn PDF document text
    • http://systemsbiology.at/uploads/assets/file/filaridotifagubediputam.pdfIn PDF document text
    • https://baodinhsolar.com/wp-content/plugins/super-forms/uploads/php/files/2afaltibenbtc3ajl2tna2kflf/budaxaz.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=mcgraw+hill+ryerson+functions+and+applications+11+pdf+downloadPDF 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_off0000ddc3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDC3 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000f5da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DA 11244 bytes
SHA-256: 798ec6d4dde872cbe06a273240d89bf58f6025f09fbdf43effc4bddad6e29a22
font_02_sfnt_off0001101a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1101A 18364 bytes
SHA-256: 175b265b709090b32192b185fd56c3750762e503b61552c3247959ab236c5d82