Malicious PDF — malware analysis report

Static analysis result for SHA-256 a36250d17ab3bf3c…

MALICIOUS

PDF

96.8 KB Created: 2021-09-02 22:06:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 4dc7b677c3dc53148ee10a05b89c6bf5 SHA-1: a52443c5ab29a5bb2ac56ec4afc2f69a03b42015 SHA-256: a36250d17ab3bf3c4896018f7b2dbb89f5fb93d4089a54a379a1ed9c508c97bc
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and a large number of external URIs, many of which point to disposable hosting or compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The presence of JavaScript suggests it may be used to facilitate the redirection or exploit vulnerabilities.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://slsnn.ru/content/file/jowuk.pdf In PDF document text
    • http://tomasmrazek.cz/userfiles/file/dasosobudazonuzifixub.pdfIn PDF document text
    • http://workprohealth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608579bc2dd89---35522509442.pdfIn PDF document text
    • http://inter-travel.hu/_user/file/vufadib.pdfIn PDF document text
    • http://faithleader.org/js/ckfinder/userfiles/files/xolaja.pdfIn PDF document text
    • http://stinpo.com/ckfinder/userfiles/files/70005841724.pdfIn PDF document text
    • http://www.catalogodecineargentino.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a219c86593---wasanifogomudekixegime.pdfIn PDF document text
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b285face737---mimafozawojakinulogomi.pdfIn PDF document text
    • https://canoe.ro/Extras/ckfinder/userfiles/files/9543114414.pdfIn PDF document text
    • https://ajitcoatings.com/uploads/38791288287.pdfIn PDF document text
    • https://samowar.me/upload/file/74418473150.pdfIn PDF document text
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/0ad3dd11571b210e1256cd88fc18c7b9/riwerajigejebevoxomosisip.pdfIn PDF document text
    • http://www.fishandcosolicitors.com/uploads/files/47903882171.pdfIn PDF document text
    • https://www.ogblfrontaliers.fr/wp-content/plugins/super-forms/uploads/php/files/nq0ru9ahlvc5rks4ut78a8fgss/80112934436.pdfIn PDF document text
    • http://udmvdpo.ru/images/files/96965105636.pdfIn PDF document text
    • http://nickelsgrafikdesign.de/ckfinder/userfiles/files/27571808191.pdfIn PDF document text
    • https://robinio.de/wp-content/plugins/super-forms/uploads/php/files/6l38dsnbdrht4sipjf50759clq/tulozobepo.pdfIn PDF document text
    • http://stonebreaker.at/vutuwejosibi.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160afa59bcfc38---74632314844.pdfIn PDF document text
    • http://gurolmumcu.com/userfiles/file/43028966968.pdfIn PDF document text
    • https://veaodaibrahma.com/uploads/image/files/vowejilinigewiviw.pdfIn PDF document text
    • http://terapie-psi.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160b6ac2160e14---tunozefiduroda.pdfIn PDF document text
    • https://mithermomix.com.mx/wp-content/plugins/super-forms/uploads/php/files/adf6484ccab055ef9dd268f47f68ab99/51850047661.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=notebook+positivo+unique+tv+s2065+manualPDF 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_off00010cf9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10CF9 20600 bytes
SHA-256: 036dc919c5534f32e891d2382754a0ffa6dfcfb2cdea0f3eb9c4277f74879344
font_01_sfnt_off000142ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x142AE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00015ac5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15AC5 11380 bytes
SHA-256: 5c45f0fbd322b017f59cdae31b9f1a8dcc0c1688d7ef03c86a1c1771f0035b33