Malicious PDF — malware analysis report

Static analysis result for SHA-256 25b5ce2e0647ab0f…

MALICIOUS

PDF

63.6 KB Created: 2021-06-24 00:23:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-26
MD5: 7f010f9fe4836af07ea10c6a06d6fe45 SHA-1: 366a37bfd209f63b1001e7793e2ee931a8168c15 SHA-256: 25b5ce2e0647ab0f47f1a5905572ddfa2d9e540c8b9009231c4660c2a6725430
156 Risk Score

Malware Insights

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

The sample is a PDF file detected by ClamAV as a phishing trojan. It contains numerous links pointing to compromised websites, many of which host other PDF files. The ML classifier also strongly indicated maliciousness. The presence of multiple links to potentially compromised CMS uploads suggests a link farm designed to distribute malicious content.

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 http://www.suffaheducation.com/wp-content/plugins/formcraft/file-upload/server/content/files/160847b154a47f---fanuzogukakolebiwafa.pdf In PDF document text
    • http://witnesstherealist.com/wp-content/plugins/super-forms/uploads/php/files/83727a21ff225cdf14c99a8c3f159a48/2383267096.pdfIn PDF document text
    • https://www.qbuildsoftware.com/wp-content/plugins/super-forms/uploads/php/files/55044b37b0fb96526cced0da3bf90322/nakenefuxev.pdfIn PDF document text
    • https://www.bakirkoytemsilcisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/160737f85ad912---meguzodufuwerapafewi.pdfIn PDF document text
    • http://aite-materials.com/upfiles/file/66933391081.pdfIn PDF document text
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/253b1cd3a4b0aa73081d990bf6d2bbab/62127533549.pdfIn PDF document text
    • https://samowar.ch/upload/file/kivafalazolodivofigiwu.pdfIn PDF document text
    • http://bwc.lt/i/butolidubafunu.pdfIn PDF document text
    • https://fatheragneliti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f5ccef1d44---pusebotifanofipekavu.pdfIn PDF document text
    • http://www.rolstoellift.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606ca64580540---58780912276.pdfIn PDF document text
    • http://dmkaudit.sk/101/upload/file/89652707994.pdfIn PDF document text
    • http://abapaposentados.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1608d55cb98424---runinugen.pdfIn PDF document text
    • http://aksaaydinlatma.com/img/editor/image/file/32483622993.pdfIn PDF document text
    • http://lawcab.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16089ca0a60d25---folemuvizinex.pdfIn PDF document text
    • https://www.okcfarmersmarket.com/wp-content/plugins/super-forms/uploads/php/files/63024915c410004960a483066de6dc4b/9476493406.pdfIn PDF document text
    • http://lnaixi.com/userfiles/file/20210620212546_38515486.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/BvfzZFkJO3s/uplcv?utm_term=biological+classification+worksheet+5+answer+keyPDF 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

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b952.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB952 5576 bytes
SHA-256: 2e5b5719fb318cc1470518880e41e953341836fb186cb5c0838d0ceba862c2d2
font_01_sfnt_off0000cc6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC6E 10820 bytes
SHA-256: 5701289c5d00ab2ac9d2164e22803ab356a3bae56a32ac83114487c450f1692b