Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8647923a71c5c9b…

MALICIOUS

PDF

75.9 KB Created: 2021-09-02 18:07:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 88b26b2d0cee0057474ba99a272bf758 SHA-1: 74d524a1c95320d6bdc669d71ba9c27b0e3110f3 SHA-256: a8647923a71c5c9bf7a3fa6a9a553962e3097abf253e3a2bfa2037584608d834
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which are part of link farms hosted on disposable domains or compromised CMS uploads, indicating a phishing or malware distribution attempt. The ClamAV detection and ML classifier strongly suggest malicious intent. While no scripts were directly extracted, the PDF structure and embedded links are indicative of techniques used to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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 https://coretry.ru/uplcv?utm_term=airasia+e+ticket+pdf PDF link annotation
    • https://www.paseppe.gr/ckfinder/userfiles/files/tutidawob.pdfIn PDF document text
    • https://altonika.pro/files/fck/file/monaveluki.pdfIn PDF document text
    • http://geluidsadviesnederland.nl/ckfinder/userfiles/files/rurekepi.pdfIn PDF document text
    • https://ce-mi.pl/uploads/userfiles/files/13183718311.pdfIn PDF document text
    • http://tiendanatacion.com/noticias/files/67815738140.pdfIn PDF document text
    • https://samavetah.com/ckfinder/userfiles/files/30984780882.pdfIn PDF document text
    • http://autoscuolavalerio.it/userfiles/files/biwobugisesiruwulifi.pdfIn PDF document text
    • http://eortak.com/img/fck_temp/file/12140042162.pdfIn PDF document text
    • https://asigurareingermania.ro/wp-content/plugins/super-forms/uploads/php/files/5i9jopm3acr0a3lgmsp0io91me/28647249001.pdfIn PDF document text
    • http://poornasreehomeoclinic.com/ckfinder/userfiles/files/67588336729.pdfIn PDF document text
    • http://ingmarcofaedi.com/userfiles/files/buzipixiwexanibirim.pdfIn PDF document text
    • http://mfplus.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160a3a11d12ce8---43986608669.pdfIn PDF document text
    • https://decoveinvestment.com/userfiles/file/7868262178.pdfIn PDF document text
    • http://hfnhsw.com/upload/files/jobuduxodujofizulamemu.pdfIn PDF document text
    • https://oknoplus-omsk.ru/wp-content/plugins/super-forms/uploads/php/files/a605b97f1adb9a0fb3703d2659bda3a4/22849866434.pdfIn PDF document text
    • http://ues-rb.ru/themes/ues-rb.ru/files/wiler.pdfIn PDF document text
    • http://h-p-n.fr/catalogue_dynamique/file/26324078864.pdfIn PDF document text
    • https://aawyx.com/sites/default/imageuser/file/febegibosekenoruk.pdfIn PDF document text
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a6d7ac602cd---bonijakidevuzorog.pdfIn PDF document text
    • http://provia-events.de/pics/fotos/1/file/42896092305.pdfIn PDF document text
    • https://gadd-asso.org/userfiles/file/34160112599.pdfIn PDF document text
    • https://www.charityweiss.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608c5aa6e1f91---77210178430.pdfIn 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://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_off0000c6fd.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC6FD 10416 bytes
SHA-256: 30d2717c417d250f17f0f6bb05c23f3fbcb8ba6574f38e87fc91a51ed314b500
font_01_sfnt_off0000dec6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEC6 17092 bytes
SHA-256: e0fbdf684c5e4b7ff296f667486b0ad83d93627b4e0fcfddbf08f1f4c5b9de19
font_02_sfnt_off00010a8a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10A8A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1