Malicious PDF — malware analysis report

Static analysis result for SHA-256 6b22bc761cf935fc…

MALICIOUS

PDF

74.0 KB Created: 2021-06-11 02:02:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-27
MD5: 6f4ff299099736bcfd048bca7aea0180 SHA-1: 268e5a4fe3ddb14b4d078ab577828aebd679837d SHA-256: 6b22bc761cf935fca5b0cfba3ad5fcc4cb0ee73ec0b4e87f29a5f97204185540
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript T1204.002 Malicious Link

This PDF file was flagged by ML classifiers and ClamAV as malicious. It contains numerous links to external websites, many of which appear to be compromised WordPress installations used for hosting malicious PDFs. The document's content, though heavily obfuscated, suggests a lure for free premium content, combined with a heuristic indicating a password-protected archive handoff, which is a common tactic to bypass security filters. The embedded URLs and the nature of the heuristics strongly suggest this document is part of a phishing campaign designed to trick users into downloading a malicious payload.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://oniceh.ru/uplcv?utm_term=free+vip+toomics+account PDF link annotation
    • https://grafitpoint.ru/wp-content/plugins/super-forms/uploads/php/files/5220896df6df6a9922579946023530d2/83466204459.pdfIn PDF document text
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/e79527901737b31a06293843a183c237/voduziteruvesidop.pdfIn PDF document text
    • http://mnogonomerov.ru/uploads/file/mokuxedogosox.pdfIn PDF document text
    • https://htlexpress.com/ckfinder/userfiles/files/98257750392.pdfIn PDF document text
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/f5ba62012be642ddccf9319f743ab3e3/zawusaxonenekupeludifepaj.pdfIn PDF document text
    • http://a-range.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb4e755be4---bedafetajikagisinumiz.pdfIn PDF document text
    • https://www.hit-education.com/wp-content/plugins/super-forms/uploads/php/files/clivctk42p8ve0ns2hjmhgslvv/25435339639.pdfIn PDF document text
    • https://www.sadcmedia.com/wp-content/plugins/super-forms/uploads/php/files/o8ieijrltvjvcu82dsekgmdt94/36916459088.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083e24b7bb15---tolivigewaserirugiruja.pdfIn PDF document text
    • https://marciasmithconsulting.com/wp-content/plugins/super-forms/uploads/php/files/70d2ac2332a1c1839506a01dc1471003/zifokuvusuvipureru.pdfIn PDF document text
    • http://coopmong.com/ckupload/files/xuzakepenor.pdfIn PDF document text
    • http://apexnepaltravel.com/userfiles/file/sesizigaloxojosaxipoko.pdfIn PDF document text
    • http://creativeindustries.ru/uploads/userfiles/file/87179944036.pdfIn PDF document text
    • http://beloit1962.com/clients/8/83/8368a4f838dea3176655029ae9e337da/File/pumijotobijilufa.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_off0000e635.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE635 5060 bytes
SHA-256: aa39a912dabc1ad3c299faef3525865a8f2be4fd8d66099ec48c8cc078ea238b
font_01_sfnt_off0000f762.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF762 10592 bytes
SHA-256: 03f6adeafd6a44334c93eb76de356792d614e3bfe9d011f1d3b5a186b8de9888