Malicious PDF — malware analysis report

Static analysis result for SHA-256 8838936222151a3b…

MALICIOUS

PDF

84.9 KB Created: 2021-09-10 14:48:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-29
MD5: 7f8511b733770d34de3101d089e691c0 SHA-1: 4d3ffbfd381191ffa0baae95c479f531bb6ac337 SHA-256: 8838936222151a3b106ed6ee6ac160a724773c6e99050ab5e70c774f70cb40e4
156 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised websites or disposable domains, indicating a link farm designed to lure users to potentially malicious content. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery. The presence of multiple external URIs and link farm heuristics supports the classification as a malicious document.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9990

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://inwebjor.ru/uplcv?utm_term=como+desbloquear+um+celular+samsung+galaxy+y PDF link annotation
    • http://mywymc.com/userfiles/file/sunex.pdfIn PDF document text
    • https://charterboatdeliverance.com/uploads/files/zonoxijivofogefoxij.pdfIn PDF document text
    • https://camping-du-lac-dijon.com/userfiles/fichiers/83049694817.pdfIn PDF document text
    • http://muabannhagiare.net/images/uploads/files/getujomuvo.pdfIn PDF document text
    • http://tetrafluoro.com/upload/files/wokuju.pdfIn PDF document text
    • http://paradisoseminatrici.it/userfiles/files/mipap.pdfIn PDF document text
    • https://vrindaindia.com/php/joseph/uploads/file/viloxibiludavefuja.pdfIn PDF document text
    • http://1night2day.com/ckupload/files/jenuza.pdfIn PDF document text
    • http://dailynewsodia.com/assets/ckfinder/core/connector/php/uploads/files/pekobuw.pdfIn PDF document text
    • http://seksdagen.nl/userfiles/file/54883205282.pdfIn PDF document text
    • https://pima-alarms.rs/slicice/file/nelonojexunag.pdfIn PDF document text
    • http://www.johnknox.ch/wp-content/plugins/formcraft/file-upload/server/content/files/1613ac798e439a---kuzufedatujobubopovonomu.pdfIn PDF document text
    • http://ljhalls.com/wp-content/plugins/super-forms/uploads/php/files/46e15aaca11b6d90f687950b1b0c6cbf/filibaridujepusosidugik.pdfIn PDF document text
    • https://www.olympusnorge.no/wp-content/plugins/super-forms/uploads/php/files/bgje732eb7inouge3e3k9e9l0q/51069193478.pdfIn PDF document text
    • http://abwingsva.com/uploads/files/36127319357.pdfIn PDF document text
    • http://revucue.com/ckfinder/userfiles/files/14050791198.pdfIn PDF document text
    • http://www.maderas-navarro.com/ckfinder/userfiles/files/xotabujaza.pdfIn PDF document text
    • http://www.biosafety.biz/ckfinder/userfiles/files/57755173033.pdfIn PDF document text
    • http://constructionone.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/161368d0fd2150---lezewojibiz.pdfIn PDF document text
    • https://www.lorenzofranzone.it/wp-content/plugins/super-forms/uploads/php/files/ea7daf7e32cae0e56652d11e1ea1bb14/99209469820.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_off0000df3f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDF3F 11156 bytes
SHA-256: df9853c1cc2d9cfa3c00760273b142e0bc3d92a715740471be7a5df6695d19c1
font_01_sfnt_off0000f8d8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8D8 20632 bytes
SHA-256: 68f058f228d1189c9f133b97ac87cfc12cfadf951f313e3e363d89c718cce838
font_02_sfnt_off00012be5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12BE5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1