Malicious PDF — malware analysis report

Static analysis result for SHA-256 af40153dfcc7b77e…

MALICIOUS

PDF

72.1 KB Created: 2021-06-14 07:05:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-24
MD5: 472f26b3a8b02f1a607c931b1d318165 SHA-1: fa89b568eef86f377b75a9a0ad1f1e59b4d7a0f5 SHA-256: af40153dfcc7b77e02c1617da3d765680c54dc75322d4827388068f2c7df10eb
164 Risk Score

Malware Insights

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

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories and presents a deceptive download button. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://queure.ru/uplcv?utm_term=psi+exam+paper+with+answer+2015 PDF link annotation
    • http://sparkpro.lv/content/file/lavapog.pdfIn PDF document text
    • https://brylka-kfz.de/wp-content/plugins/formcraft/file-upload/server/content/files/16097e3e932264---34184598816.pdfIn PDF document text
    • https://akproauto.com/nbloom/fckuploads/file/59708287305.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606ed6748c873---nizuvirodifewuzemu.pdfIn PDF document text
    • https://marksiegeldds.com/wp-content/plugins/super-forms/uploads/php/files/61b5e45049a2a87860b8e917af7942f3/31813791537.pdfIn PDF document text
    • http://fincasotilloviejo.es/files/sotillo/_repo/file/pufuwugunazixokozafinaf.pdfIn PDF document text
    • https://3dreamvr.com/wp-content/plugins/super-forms/uploads/php/files/02dba4438cc3250868a8e0a65cfe1557/xaloxufelorijakep.pdfIn PDF document text
    • http://cadeco.com/testingsites/advantage_aviation/assets/media/file/vataluwopevejoso.pdfIn PDF document text
    • http://sungsam.net/userData/board/file/jolifabezoridipix.pdfIn PDF document text
    • http://ash-graphy.com/userfiles/file/83082249742.pdfIn PDF document text
    • https://sip7.pl/autoinstalator/sip7.online/wp-content/plugins/super-forms/uploads/php/files/1f1db290ce65625b54eaaf99a1cc03e0/kodimuvojij.pdfIn PDF document text
    • http://subventionsbetrug.de/wp-content/plugins/super-forms/uploads/php/files/6bj65380dfc2111o535cifkjo2/8891895013.pdfIn PDF document text
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1608354c2a328f---dotojonupujufomozofemuza.pdfIn PDF document text
    • https://howardsteeves.com/wp-content/plugins/super-forms/uploads/php/files/28cd49ef299805179cf6a5ed738ef7b8/bumunavigatox.pdfIn PDF document text
    • http://www.majorisinvestimentos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b3928e7f52c---13531054094.pdfIn PDF document text
    • https://stopserv.ru/files/file/vibesub.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_off0000d9cb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CB 5640 bytes
SHA-256: 0f38eff69f9760ef78084e2dccd5cf22f434013a76132422f8a8e962d248fc2a
font_01_sfnt_off0000ecef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECEF 10944 bytes
SHA-256: aa8b8a0be7d572af12065784ba3dbe95e1f64401617c696774c53dc966f3cef5