Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1f7f2ffc369ff3a…

MALICIOUS

PDF

86.4 KB Created: 2021-10-05 10:51:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: f35207d27a08c3e8432f0c19bbb1fc1b SHA-1: d054c1b9f893c183938ca2ad988a59e7c4c9b41b SHA-256: b1f7f2ffc369ff3a5061d6e9d333fe23e7da576ff6a5e84898b4a0a32c471c8d
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample contains embedded JavaScript, a common technique for executing malicious code within PDFs. It also features a link farm pointing to multiple distinct hosts, many of which appear to be compromised CMS upload directories. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://www.santaterezinha.com.br/js/ckfinder/userfiles/files/fenipebigokugetonaf.pdf In PDF document text
    • https://www.temsilcisitesi.com/wp-content/plugins/formcraft/file-upload/server/content/files/161597ce52695e---garolefojutajadi.pdfIn PDF document text
    • http://ssanadia.in/userfiles/file/55603197570.pdfIn PDF document text
    • http://homeshopeez.com/uploaded_files/userfiles/files/69918310494.pdfIn PDF document text
    • http://e-baze.lv/images/site/file/36251139183.pdfIn PDF document text
    • https://angkorphotographyguide.com/userfiles/file/23733669437.pdfIn PDF document text
    • http://cafesezony.ru/fck_editor_files/files/26088336985.pdfIn PDF document text
    • https://guruamardaspublicschool.com/userfiles/files/niwaduf.pdfIn PDF document text
    • https://la-klamm.org/Files/files/88115222570.pdfIn PDF document text
    • http://nanoscopy.ru/uploads/files/foloripew.pdfIn PDF document text
    • http://pooinkki.com/upload/imagesource/file/dalig.pdfIn PDF document text
    • http://em-mould.com/ckfinder/userfiles/files/3014162400.pdfIn PDF document text
    • http://robalton.es/Albums/images/file///37423522891.pdfIn PDF document text
    • http://psychologyforeverybody.com/ckfinder/userfiles/files/damurimonepurewobi.pdfIn PDF document text
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161421ddddc57d---39243171478.pdfIn PDF document text
    • https://koltoztetes-szallitas-lomtalanitas.excore.hu/ckfinder/userfiles/files/89824873030.pdfIn PDF document text
    • https://fitvital.hu/userfiles/files/sadaguziz.pdfIn PDF document text
    • https://fitvital.hu/userfiles/files/30632988494.pdfIn PDF document text
    • https://miminku5.com/contents/files/fexib.pdfIn PDF document text
    • http://tajesink.com/Uploadfiles/files/14120144374.pdfIn PDF document text
    • http://siciny.eu/userfiles/file/41621527082.pdfIn PDF document text
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a802e7164f---97731431863.pdfIn PDF document text
    • https://leuphuotcamap.com/uploads/image/files/fegaviduw.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=buy+back+share+meaningPDF 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://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_off0000e57d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE57D 10912 bytes
SHA-256: c73d9cdfb7fe00f374941868b5917f799e5231f913e8566625d0a55dae0164ec
font_01_sfnt_off0000fea6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFEA6 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000116b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116B8 20304 bytes
SHA-256: 34260ff241ff31a63c3326517a8a0a21f6b860c71fdc3226aebdf350868f4ae3