Malicious PDF — malware analysis report

Static analysis result for SHA-256 1b8b229477db37b0…

MALICIOUS

PDF

81.2 KB Created: 2021-05-27 17:45:37 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: 5de2e33578b34cc532b21555a735b12f SHA-1: a6f586fcab4d81b0aac227551fdf9860a87be6e4 SHA-256: 1b8b229477db37b0d18574dc79a0c7dc55b137d15a636b8f145b7a9fa034527d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains a large number of links, many of which point to compromised WordPress sites, indicating a link farm designed to distribute traffic. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. The document body appears to be obfuscated or corrupted, providing no clear user-facing content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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://www.keystonecare.co.uk/wp-content/plugins/super-forms/uploads/php/files/0db113d0c3fc97c1c2b29f097def94e5/mezukukagikatum.pdf In PDF document text
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/64836f15d205a012d90b89757abfbc0f/fuzugiwiwufafe.pdfIn PDF document text
    • https://www.isgs.org/wp-content/plugins/super-forms/uploads/php/files/c411958d0184d35859fc2f437eac730c/befaf.pdfIn PDF document text
    • http://amfmeg.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607b27b50ef3f---dudekezogow.pdfIn PDF document text
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607070108f691---54402419400.pdfIn PDF document text
    • http://localhomesales.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160986bd4289d9---tovuzefolotiwopowonez.pdfIn PDF document text
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/6etorqceej46a0ukulluq8eij5/fotafopedowamedawafepanam.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/b721usfllcauq0drc7fp369ep7/notixaposozumamos.pdfIn PDF document text
    • http://amazingindiaphotos.com/amazingindiaphotos//upload/fckimage/file/zajum.pdfIn PDF document text
    • https://halobysciton.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096e32cb555f---golufaruxabokugo.pdfIn PDF document text
    • https://www.popcaffe.it/wp-content/plugins/super-forms/uploads/php/files/be9ea014831cdcf080b1e69f39659102/tusotadovobug.pdfIn PDF document text
    • https://enville.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d751554fbb---67164491590.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/1606e6f4e5bf59---5871311165.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/ca1efebf452bccbe4a934afd929d897e/68383133387.pdfIn PDF document text
    • http://www.opencalgary.org/wp-content/plugins/formcraft/file-upload/server/content/files/160840284c31cc---91843283320.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=ejercicios+de+razonamiento+matematico+resueltos+para+segundo+de+secundariaPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f998.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF998 5476 bytes
SHA-256: 5167329f8b2235eebcccf77aa678963c0aae164d6bf735b19ec0330a4b35ae98
font_01_sfnt_off00010c33.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10C33 12540 bytes
SHA-256: 585090237aeae053082d21a3afe963e5f040e19da3b14d7e4939c559bab85daf