Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef1704f17b97a6c2…

MALICIOUS

PDF

76.1 KB Created: 2021-06-15 20:07:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-12
MD5: fe7634f03bc2f13348ae4f08538fdfdf SHA-1: 268a624540415f6f65e40c6c3d11d314aeecaa0a SHA-256: ef1704f17b97a6c26d62a0bc2864598c0bad7399fb7d68e57718c89ca5cb25be
156 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous external URIs and link farms pointing to potentially compromised or disposable hosting, suggesting a phishing or malware distribution scheme. The presence of embedded JavaScript, though not fully analyzed due to obfuscation, likely facilitates the download and execution of further malicious payloads.

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://medvor.ru/uplcv?utm_term=essentials+of+toxicology+pdf PDF link annotation
    • https://porterbrothersltd.com/app/webroot/uploads/pafevugunusugupiw.pdfIn PDF document text
    • http://ildungrice.com/fileupload/fckeditor/file/13109170998.pdfIn PDF document text
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1609d2eca78ada---lufuxafirofuloka.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae7a432f851---malazovawijesudeg.pdfIn PDF document text
    • http://alsumiri.net/wp-content/plugins/super-forms/uploads/php/files/00c5c4d69f7baebb98f1ad32e07937b1/3861885204.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160983264d4120---gubamab.pdfIn PDF document text
    • http://18554080.com/userfiles/file/34970823324.pdfIn PDF document text
    • http://baharemadinah.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607aed0bb9914---97142579518.pdfIn PDF document text
    • http://elfuklid.cz/foto/Image/file/53928736073.pdfIn PDF document text
    • https://extremetour74.ru/wp-content/plugins/super-forms/uploads/php/files/b7788e429e377f3f1879c0b73cb674f6/39153253687.pdfIn PDF document text
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/e8d284800b6b1a04b926640a1f3f5c9e/39998487025.pdfIn PDF document text
    • https://nnkcreations.com/userfiles/file/vegem.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/2fe79be02dab4f6c7295e399e8f794b0/41984703589.pdfIn PDF document text
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160765fb06d9c7---bujozemavufazaduwe.pdfIn PDF document text
    • https://www.gs-gleichmann.de/wp-content/plugins/formcraft/file-upload/server/content/files/16073fd5fd8673---fipodemavepubofajatelaxi.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_off0000ebf6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEBF6 5356 bytes
SHA-256: 81a4cd30ee10192513d868fba58c023d230753036cb0e310e94d9ae77bc3ac0f
font_01_sfnt_off0000fe57.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFE57 11172 bytes
SHA-256: dc4fea864991be871f68d34c035427c580cb57a45444b8af490803da5cd2c904