Malicious PDF — malware analysis report

Static analysis result for SHA-256 a5b843e3036026fc…

MALICIOUS

PDF

78.9 KB Created: 2021-06-24 10:18:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-27
MD5: ecb2f661c4d52a09a6e512ddb021b2aa SHA-1: f2bc2c3256dfadf7f1d846fe4459506d71ea1306 SHA-256: a5b843e3036026fc1f39288adbbbb3177326ca206abc8c298a5672d692e6f210
164 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to multiple compromised WordPress sites, suggesting an attempt to distribute malicious files. The ML classifier and ClamAV detection strongly indicate malicious intent. The presence of embedded URLs and the heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' further support the conclusion that this document is part of a phishing or malware distribution campaign.

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://mls.lighting/wp-content/plugins/super-forms/uploads/php/files/93d7b778832a04243233967e8809004b/dabukowerimivaz.pdf In PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/1609a9fcf09e1c---siruvesafotus.pdfIn PDF document text
    • https://www.saammohaseb.ir/wp-content/plugins/super-forms/uploads/php/files/30adb26398e2374ba8529000e446118d/vamuviwurulanoleno.pdfIn PDF document text
    • https://www.alpha-dynamics.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16080a0f0ef169---wirutijenegite.pdfIn PDF document text
    • http://stopasbestos.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1609668d063bd0---16819098501.pdfIn PDF document text
    • http://www.thelawchamber.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f69694f9d4---62684684441.pdfIn PDF document text
    • https://dedywiredja.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608428d434777---fofulaxen.pdfIn PDF document text
    • http://xn--80ackbssfuieecff0e8c.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/jkc7hbm6vmarphs88jlvuq31l2/juwozamorazonojasow.pdfIn PDF document text
    • https://seroinstitute.com/wp-content/plugins/super-forms/uploads/php/files/024d2528eb288b447139a0246d02aa40/lewukedu.pdfIn PDF document text
    • https://deedpoll.sg/wp-content/plugins/super-forms/uploads/php/files/3df4d2f8f8c5562422367df8457a7000/82895168960.pdfIn PDF document text
    • https://bistro-8.com/wp-content/plugins/super-forms/uploads/php/files/606ad47de158ec5136619def3ec05f7c/kavifaxoludod.pdfIn PDF document text
    • https://www.sahabatkeluargahomecare.com/wp-content/plugins/formcraft/file-upload/server/content/files/16084d7ae89654---22252944298.pdfIn PDF document text
    • https://medok18.ru/wp-content/plugins/super-forms/uploads/php/files/42404dd8ee8afafefa965c7951cf4bc5/molofuforopidetorodi.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070a885eb44b---36048434644.pdfIn PDF document text
    • http://onestudent.dk/userfiles/file/83736273248.pdfIn PDF document text
    • https://boldvision.tv/wp-content/plugins/formcraft/file-upload/server/content/files/160ae05c8b6287---30595030388.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/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=f+clef+and+g+clef+notesPDF 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
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e160.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE160 5048 bytes
SHA-256: f921dd83bc2087d87ff847eb5223da6136ce21c4b937fe8b4c1fcbdf9ff45d87
font_01_sfnt_off0000f2a7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2A7 10844 bytes
SHA-256: d1bede743f8928bf2125c2af8e3e6550888da7e4ac824e8bd0c5267e51808f8d
font_02_sfnt_off000117d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x117D0 16200 bytes
SHA-256: dcf5bf9068761a66a65f40ee5aed8df972f266ddb8aeda1fcf15af54b1a3ac9a