Malicious PDF — malware analysis report

Static analysis result for SHA-256 decb6ad0c5c3ece7…

MALICIOUS

PDF

74.6 KB Created: 2021-09-16 14:29:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 1925be78b231046e936e81dd97917772 SHA-1: 064e801a1b45ce221f9243c633905f6a319f5224 SHA-256: decb6ad0c5c3ece767dc7bbbc48814a3e9fc1d31482e164044917dc790e25e49
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs that point to various websites, many of which appear to be part of a link farm designed to redirect users. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution. The presence of multiple compromised CMS upload links further supports the malicious nature of the PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9963

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://infrive.ru/uplcv?utm_term=autocad+for+android+apk PDF link annotation
    • http://otworz-biuro-podrozy.pl/userfiles/file/42135955981.pdfIn PDF document text
    • https://glearningsolutions.com/userfiles/files/saxowuvusibipurolupip.pdfIn PDF document text
    • https://scout-educationguide.com/userfiles/file/razefomik.pdfIn PDF document text
    • http://sinorarechem.com/upload/files/48623243763.pdfIn PDF document text
    • https://artasedanasingaraja.com/uploadfck/file/sudemamujuwejuvabasoxipuf.pdfIn PDF document text
    • https://www.beadvised.co.uk/wp-content/plugins/super-forms/uploads/php/files/7657d4a272468d5c59b4c941d58b7aff/8425063092.pdfIn PDF document text
    • http://studioingegneriavaragnolo.com/userfiles/files/wusakoregepupofedezur.pdfIn PDF document text
    • https://sunarchegypt.com/userfiles/file/73215738146.pdfIn PDF document text
    • http://snabsz.ru/ckfinder/userfiles/files/gosikurorus.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210903_E0D2E72364AE3340.pdfIn PDF document text
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130300ca815f---nogutarosipozi.pdfIn PDF document text
    • http://bienchidan.org/uploads/files/28057865144.pdfIn PDF document text
    • https://gamma-electronics-eg.com/userfiles/files/dazizobejotakikezaripu.pdfIn PDF document text
    • https://balbok.net/admin/ckfinder/userfiles/files/migejoluwurejiwuduzubel.pdfIn PDF document text
    • http://sz-nuoyi.com/Upload/file/2021090110031581945.pdfIn PDF document text
    • https://crbz.ru/userfiles/file/garotepamezinelizo.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/baf9db05fd24c863f86f327706edb76d/47664390759.pdfIn PDF document text
    • http://bluebirdcanada.com/FileData/ckfinder/files/20210911_0E593FCFBA88DDE7.pdfIn PDF document text
    • https://razredna-nastava.net/files/82727428827.pdfIn PDF document text
    • https://biocenfis.es/uploads/assets/file/84431722694.pdfIn PDF document text
    • http://jadever.vn/Images_upload/files/dalasuzikowul.pdfIn PDF document text
    • http://www.agot.pl/upload/file/monizipurukebi.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_off0000b9de.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB9DE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000d1f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1F5 10440 bytes
SHA-256: 3c3c83b3452c9d19dd16774a7dbbe6ac81ef6d3f7199afaff970e5ad32843697
font_02_sfnt_off0000e9c0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE9C0 19784 bytes
SHA-256: 10fe3faa346b2559bb79870a55e0d8c9fe06c730ad167501e7302883d3f01b25