Malicious PDF — malware analysis report

Static analysis result for SHA-256 dca1a4bbf4e00e03…

MALICIOUS

PDF

63.9 KB Created: 2021-06-19 16:04:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: 4325c7dbe375ce69c4e0fb44b371ec6d SHA-1: 701f834089a54bfaa6a35b83bddb2715a587df91 SHA-256: dca1a4bbf4e00e03a499f0f2d162c525abda37bcd9a5cb2c66d9c83be1de0e1d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

This PDF file was detected as malicious by ML classifiers and ClamAV, indicating a phishing or trojan distribution attempt. It contains numerous embedded URLs, many pointing to compromised WordPress sites, suggesting it functions as a link farm to distribute further malicious content. The presence of external URI heuristics and the compromised CMS upload link farm heuristic strongly support this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://ketchas.ru/uplcv?utm_term=rick+ross+magnificent+mp3 PDF link annotation
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/16463794a09725f0fad28eb3c90983d3/52730377844.pdfIn PDF document text
    • http://www.musicmaestrodiscos.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160a7d90e35f2f---59061284526.pdfIn PDF document text
    • https://bestcoloringpages.com/userfiles/file/munaxowumunufexe.pdfIn PDF document text
    • https://selectwifi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f5ea0d2826---jonevokekuzijaxajodifel.pdfIn PDF document text
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/160c7709bf0760---fepibo.pdfIn PDF document text
    • https://fellowpeo.com/wp-content/plugins/super-forms/uploads/php/files/dd1ab125997b9d8e748b52c667f73029/valararalumi.pdfIn PDF document text
    • https://chefinhogourmet.com/wp-content/plugins/super-forms/uploads/php/files/d8a6e798b07e5c4afc0a016dcba25484/tujosikopumedopo.pdfIn PDF document text
    • https://rhythmcprandfirstaid.com/wp-content/plugins/super-forms/uploads/php/files/9ec8619c6706738338a7de8df4938a7b/joroxefunusoxowesasefafur.pdfIn PDF document text
    • https://bawwabatrizq.com/userfiles/file/zimopebukizog.pdfIn PDF document text
    • http://industrialdevices.in/uploads/duguresorelimuvanigi.pdfIn PDF document text
    • http://pcccphucvinh.com/upload/files/80703714777.pdfIn PDF document text
    • http://www.eflox.net/wp-content/plugins/formcraft/file-upload/server/content/files/16070d09b6ebf2---57460666027.pdfIn PDF document text
    • http://amindoost.ir/images/upload/files/45265366772.pdfIn PDF document text
    • https://backcountryplayground.com/wp-content/plugins/super-forms/uploads/php/files/3dc1a53e1a685e3075aa64d6379e6934/25129814051.pdfIn PDF document text
    • https://www.sir.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16078d883e0739---12382142086.pdfIn PDF document text
    • http://novussiteyonetimi.com/uploads/file/zaveporuvopozirorukev.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000bcb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBCB0 5540 bytes
SHA-256: a81fbf18b86a7f7165398f1c516889347b776350afb716d2f3c86a8cda04ce70
font_01_sfnt_off0000cf84.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCF84 10444 bytes
SHA-256: c58c7b26f1bc3f0c60f02fc2cdc929c9d17b1a7b9656fbdf37874c25fb03df06