Malicious PDF — malware analysis report

Static analysis result for SHA-256 15b825ec50193efb…

MALICIOUS

PDF

83.2 KB Created: 2021-09-07 16:17:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: d163b010cf90c3113f5c92a76fdbfc0c SHA-1: 9e6d25d0447933da16e7a3824196eb3620d07ada SHA-256: 15b825ec50193efbe3c8feb6d1d99d398a3883b0485548fefe4b89e7101444e6
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites and disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URI heuristics point towards an attack pattern involving redirection to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://smidgel.ru/uplcv?utm_term=barcarolle+duet+pdf PDF link annotation
    • http://paliukenas.lt/i/File/73734372259.pdfIn PDF document text
    • http://cnpair.com/userfiles/file/51793353663.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/rizaluvenepedu.pdfIn PDF document text
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/160b668ab39b90---wuwakofe.pdfPDF link annotation
    • http://akkoryazilim.com/userfiles/file/19066277349.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608e0a733207b---towuparu.pdfIn PDF document text
    • http://slowjamsundays.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c7183bc081---80961124267.pdfIn PDF document text
    • https://hagabb.ro/ckfinder/userfiles/files/94167785957.pdfIn PDF document text
    • https://evg-prague.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160aa4379b5b9e---92030536224.pdfIn PDF document text
    • http://daiichihr.com/uploads/news_file/13788699853.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/13c74544a97c497f81c466b717d74875/visezogenuzetu.pdfIn PDF document text
    • https://get-insurance.in/ckfinder/userfiles/files/42427523450.pdfIn PDF document text
    • https://mystruggle.uk/indigo/ckfinder/userfiles/files/juwufirojefibopexetepe.pdfIn PDF document text
    • https://drainscovers.com/wp-content/plugins/super-forms/uploads/php/files/dab3cb50476d001e11c8b22f38accfd5/98472380985.pdfIn PDF document text
    • http://www.drop-lok.com/wp-content/plugins/formcraft/file-upload/server/content/files/160818262650de---wetupobosedu.pdfIn PDF document text
    • http://didocrosby.com/imagenes/file/nuvap.pdfIn PDF document text
    • http://www.iuoelocal870.com/kaizen/ckfinder/userfiles/files/1940949789.pdfIn PDF document text
    • http://ccspatti.org/userfiles/file/dimimunifujik.pdfIn PDF document text
    • http://www.depomatrial.com/file/58744924486.pdfIn PDF document text
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/16123838cda5fd---54874111897.pdfIn PDF document text
    • https://sieuthimaycafe.vn/uploads/file/29095860749.pdfIn PDF document text
    • http://audidalys.lt/ckfinder/userfiles/files/46514640774.pdfIn PDF document text
    • https://ludifrance.fr/userfiles/file/ponikafasotuzeri.pdfIn PDF document text
    • https://psychologgia.pl/Upload/file/83664956956.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_off0000dd54.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD54 19072 bytes
SHA-256: 6fc45ea3a69fe5829b0aa26e9a3aba39b1fcf501403f1ed7a9e0e894cee0d522
font_01_sfnt_off00010fae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10FAE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000127c5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x127C5 10404 bytes
SHA-256: df7ddb3a0b0453cecbca2c737d1cd086d3f3f9e82901a7a2411c177aa8797a69