Malicious PDF — malware analysis report

Static analysis result for SHA-256 f1efcf5e52f32a61…

MALICIOUS

PDF

134.5 KB Created: 2021-06-11 08:24:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-05
MD5: 7db2cbb8baaa824f84111aae9ea19cae SHA-1: 71640733d707e1b1e0a1fd4be9cb72b54bf32335 SHA-256: f1efcf5e52f32a615ab4a38da16683e5008e1675a80e2dddba03cd4005c5fca0
156 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier. It contains numerous links pointing to compromised websites and disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of embedded URLs and the nature of the heuristics indicate a phishing or malware distribution attempt, likely initiated via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

Heuristics 6

  • 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.
  • 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://nomylo.ru/uplcv?utm_term=cambridge+english+compact+key+for+schools+pdf PDF link annotation
    • https://www.formwork.co.uk/wp-content/plugins/super-forms/uploads/php/files/cgklsp9g1ntrbmgi4vfrflitbs/97483854074.pdfIn PDF document text
    • https://www.xcelsus.de/wp-content/plugins/formcraft/file-upload/server/content/files/16098b14380436---munobazebolusemosotid.pdfIn PDF document text
    • http://www.hkwebdesign.com.hk/wp-content/plugins/formcraft/file-upload/server/content/files/16093a5bb848fc---33967914203.pdfIn PDF document text
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/360fc0f0cba1dc249c95c425fe5d3f56/tazosesujedalotakejesofev.pdfIn PDF document text
    • https://directprocessors.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bb40cfe5d72---73911408483.pdfIn PDF document text
    • http://jrpst.pl/userfiles/file/wokiguvedinawagoze.pdfIn PDF document text
    • https://dmddsgn.com/wp-content/plugins/super-forms/uploads/php/files/ca35cc60f9464b0bc65277b9475c3dc1/zisirad.pdfIn PDF document text
    • https://wurstfargo.com/wp-content/plugins/super-forms/uploads/php/files/2ab55e4b138b0c5c2b1ffe5866c23229/32546713257.pdfIn PDF document text
    • https://rmissio.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16070be3ce9164---linurosoxijajogigujarel.pdfIn PDF document text
    • http://svsteinfurth.de/radsportfiles/file/bobolunilozigix.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/el7qrl68g3u0g3pvj53eougbrd/83791264913.pdfIn PDF document text
    • https://ebooksweb.net/files/file/xawijevimitil.pdfIn PDF document text
    • http://hellnocancershow.com/wp-content/plugins/formcraft/file-upload/server/content/files/160805dcb9f7b3---ruzurimebu.pdfIn PDF document text
    • https://gfow.om/wp-content/plugins/super-forms/uploads/php/files/pnsrkeurosbeadfbmet0cv60gm/wuradinaxenijivixige.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1608b10d638afc---vidutesezabixuvafemaw.pdfIn PDF document text
    • http://karmand24.ir/basefile/ehotel724ir/files/73612957619.pdfIn PDF document text
    • https://x-software.cz/data/file/nevajapopesowigavalevo.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160773ee49496b---samerelomagiwujoj.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_off0001d22d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1D22D 5780 bytes
SHA-256: 54416f75989a230dcde9b1d0f1d8a7ae3a257f1dc4dec963c6cdd46ae388eaa5
font_01_sfnt_off0001e5ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1E5AB 12068 bytes
SHA-256: 8ab83a6e207548aa91131c501237cef98f01c501894bdd6c5e30a2a0f332f4b8