Malicious PDF — malware analysis report

Static analysis result for SHA-256 b3d83610eb8bcdea…

MALICIOUS

PDF

87.4 KB Created: 2021-06-22 13:53:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-07
MD5: 192b2d1d324966cc4863663f20731e18 SHA-1: 6c3367cf5a5292759a26704ebfa7a3dcfdac3a95 SHA-256: b3d83610eb8bcdea19fee86b1298b3bc891fc7ab78da98580bdaaab6355b20af
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains a link farm designed to appear as a download for 'English book 1st year pdf download', which is a common lure for phishing or malware distribution. Several URLs point to compromised WordPress sites and disposable hosting, indicating a pattern of malicious link distribution. The ML classifier and ClamAV detection strongly suggest malicious intent.

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 http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee245a5474---21736357798.pdf In PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/3232fdb166249a0ee0555b3ea7d906b6/72715970424.pdfIn PDF document text
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/f7098038ed76dc3e28137aa3bd2a10bd/91593169477.pdfIn PDF document text
    • http://bielwod.com/userfiles/file/nelesebulod.pdfIn PDF document text
    • https://techson-cctv.com/upload/file/77091348558.pdfIn PDF document text
    • https://www.hediyevideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609183bcdfd47---pujutin.pdfIn PDF document text
    • https://htfcompact.com/wp-content/plugins/super-forms/uploads/php/files/16ca760647e62fecb2ca5f6dd01280dc/71792860567.pdfIn PDF document text
    • http://rayzerfamilyreunion.com/clients/0/08/08e2d5bcffca37c2e1a82d364f4296c6/File/75975676139.pdfIn PDF document text
    • https://abeess.com/userfiles/file/bibajo.pdfIn PDF document text
    • http://mobydick-band.de/fckdata/file/34292685841.pdfIn PDF document text
    • https://revapackers.com/wp-content/plugins/super-forms/uploads/php/files/m9kg8998afe10g23lmqrcspt2n/musojamimunit.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/16073773a22d54---52296795697.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/160926793c6b1e---78542225419.pdfIn PDF document text
    • https://hmjrgoldhockey.org/wp-content/plugins/super-forms/uploads/php/files/84cd81132e93cf78d56fe90d94c1b1f2/regubujinure.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=english+book+1st+year+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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000107dd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x107DD 5500 bytes
SHA-256: 4da05ce77e180bad1940c9b1cf2ae0a979d688bb4a3a229f1463657fc5947efe
font_01_sfnt_off00011a95.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A95 11304 bytes
SHA-256: 941231628a079f1d8284fa94134b57b359353ab3fffb7f86a6a7b728d51dc394
font_02_sfnt_off000140b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x140B9 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3