Malicious PDF — malware analysis report

Static analysis result for SHA-256 0a359c1148fee6ec…

MALICIOUS

PDF

72.3 KB Created: 2021-09-15 11:09:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 5556f7d143062d1643fa449ff28bbc24 SHA-1: ce112626c83dc7f72612e64a5671c37424e7042b SHA-256: 0a359c1148fee6ec8cb60b4ff023a476305050d291be62a1079cf35eab3d5368
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with numerous URLs pointing to compromised websites, suggesting a phishing or malware distribution scheme. The document body is heavily obfuscated, preventing analysis of specific content, but the overall structure and URL targets strongly suggest a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://sanitaerprofi.ch/fckeditor/editor/images/file/5833142971.pdf In PDF document text
    • http://kpdb.org/userfiles/files/75241702977.pdfIn PDF document text
    • https://argekaucuk.com/nbg/upload/files/92969057628.pdfIn PDF document text
    • https://terlickodds.cz/www/www/fckphotos/file/76378531685.pdfIn PDF document text
    • https://anmoul.com/userfiles/file/92560493407.pdfIn PDF document text
    • http://birnagarcollege.in/userfiles/file/memotufinowis.pdfIn PDF document text
    • https://deniz-sogutma.org/img/userfiles/file/78900495527.pdfIn PDF document text
    • https://corcreation.twbiz.me/data/fckeditor/files/20210902_234523.pdfIn PDF document text
    • https://ispartaprefabrik.com/ckfinder/upload/files/dedidozexuz.pdfIn PDF document text
    • http://laibros.com/ckeditor/userfiles/files/turikirisanivowuregiv.pdfIn PDF document text
    • https://firmabudowlanawalczak.pl/web/uploads/files/gidaxibomewetemixi.pdfIn PDF document text
    • http://effekt-film.de/files/file/sutoninufow.pdfIn PDF document text
    • http://aa-nusd.jp/84365499663.pdfIn PDF document text
    • http://bannhuaduong.net/upload/files/10274536189.pdfIn PDF document text
    • http://littlepearlspublishing.in/data/eimages/file/14528176986.pdfIn PDF document text
    • https://iohrp.org/f_files/files/43237791543.pdfIn PDF document text
    • http://cuoredicane.it/userfiles/files/relobuwojuvuzufogane.pdfIn PDF document text
    • http://matrixuniverzum.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16140503ac72c0---danigas.pdfIn PDF document text
    • http://drxzhang.com/userfiles/file/lebiwen.pdfIn PDF document text
    • https://capital-publishing.com/ckfinder/userfiles/files/44330251792.pdfIn PDF document text
    • https://tfnd.org/wp-content/plugins/super-forms/uploads/php/files/e1719cd9fdc5b3a74cc08abccd6a81b6/42489774023.pdfIn PDF document text
    • https://brihat-group.com/assets/userfiles/files/damijav.pdfIn PDF document text
    • https://qigoodteam.com/uploads/files/202109081550268077.pdfIn PDF document text
    • http://gf-location.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16141840892614---89142303737.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/cv9VXjIrmdE/uplcv?utm_term=how+do+you+clear+your+history+on+your+phonePDF 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_off0000b923.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB923 10900 bytes
SHA-256: 7d83d6d42550f66fcf4fde4ada40c93ec28ec5c04edb99fba662772e9e61c00a
font_01_sfnt_off0000d253.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD253 15996 bytes
SHA-256: ec5926e8db032c0d04160412935658f2e2b132b48dccc2e581318cf01ee6050f
font_02_sfnt_off0000fb60.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB60 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1