Malicious PDF — malware analysis report

Static analysis result for SHA-256 c4abd226c4200d19…

MALICIOUS

PDF

82.5 KB Created: 2021-09-19 09:36:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: a1d1cdec5edaf3d5e181a1bc1d037933 SHA-1: cf1a4c003d5931c21424b85bc3b52df5b9aa127b SHA-256: c4abd226c4200d1993472d41f3915f5096d4740ee2cfb4b096c1a7a9abd2fd13
142 Risk Score

Malware Insights

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

The PDF contains embedded JavaScript and numerous external URLs, many of which are part of a link farm, indicating a malicious intent to redirect users to potentially harmful content. The ML classifier and ClamAV detection strongly suggest this PDF is malicious, likely serving as a lure for phishing or malware distribution. The presence of embedded JavaScript points to its use in exploiting vulnerabilities or executing malicious code.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://cructi.ru/uplcv?utm_term=monster+legends+unlimited+everything+apk PDF link annotation
    • http://tavio.su/files/file/69874399147.pdfIn PDF document text
    • http://xn--80aap0abfiql8h.xn--p1ai/admin/ckfinder/userfiles/files/16640482327.pdfIn PDF document text
    • http://olgapolyakova.com/files/files/furasokavawexovo.pdfIn PDF document text
    • https://markaoyun.com/calisma2/files/uploads/palagazos.pdfIn PDF document text
    • http://vce34.ru/attachments/file/43560172917.pdfIn PDF document text
    • http://wmc21.com/ckupload/files/gugitewavilatetu.pdfIn PDF document text
    • http://www.hro.ait.ac.th/js/ckfinder/userfiles/files/xuxekabakudukorelodaxaza.pdfIn PDF document text
    • http://jingluo.net/uploadfiles/files/63467336548.pdfIn PDF document text
    • https://myclubowners.com/userfiles/files/zuvimudoduwumef.pdfIn PDF document text
    • https://kimcert.com/E/file/21542895561.pdfIn PDF document text
    • http://mikailang.net/userfiles/file/20210918193846_1462902374.pdfIn PDF document text
    • https://giritrademark.com/content_files/files/fesubiforupumojufasat.pdfIn PDF document text
    • https://portofcrotone.com/dati/upload/file/rokebulub.pdfIn PDF document text
    • https://tutorsbureau.net/userfiles/file/lopamalejoz.pdfIn PDF document text
    • http://ohsongpharm.com/ckfinder/userfiles/files/kipaxijivul.pdfIn PDF document text
    • http://jd6618.com/jd6618/file/2021-9/file/LwpCms2021_09_07_18_59_36_3706.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/16138aaa98cf04---9947351441.pdfIn PDF document text
    • https://editora-arara-azul.com.br/site/admin/ckfinder/userfiles/files/78232463848.pdfIn PDF document text
    • http://aranysolyomfeszke.hu/editor_up/35584641979.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16144b4761422c---bimokub.pdfIn PDF document text
    • http://app0.linkeo.it/ckfinder/userfiles/files/97072339002.pdfIn PDF document text
    • http://em-mould.com/ckfinder/userfiles/files/donegoxa.pdfIn PDF document text
    • https://jewfri.kr/files/image/files/44335948599.pdfIn PDF document text
    • http://ridendo.cz/files/file/2118814466.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_off0000dc2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDC2C 11204 bytes
SHA-256: a61beaf6ec63774d3d4e13e385540e66e6fa1feb3c84feeb544f9abe6d2c1c7a
font_01_sfnt_off0000f608.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF608 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00010e1a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10E1A 17888 bytes
SHA-256: 1ff9aec87b58ef2a5767662fe6d026dec04f6e48881dc1d3571b69d2a5838ec6