Malicious PDF — malware analysis report

Static analysis result for SHA-256 e1704d9271e61d03…

MALICIOUS

PDF

71.3 KB Created: 2021-10-04 21:50:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 3fd1338bc157596ee24dc287e0b6cff7 SHA-1: 9794ff5b31a0e83b2603e0013be64ac28d197a6f SHA-256: e1704d9271e61d03848844f77c8e70a69de88e72b2161902ca5082f3b5bd5d71
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was identified as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, directing users to multiple external websites, some of which are hosted on compromised CMS platforms or disposable domains. The presence of numerous URLs, many pointing to PDF files, suggests an attempt to distribute malicious content or conduct phishing operations.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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://korean-school.hu/hangul/userfiles/file/51551373968.pdf In PDF document text
    • http://novelinternationalschool.com/ckfinder/userfiles/files/1078792660.pdfIn PDF document text
    • http://isotope3.pm-ural.com/uploads/files/11010724736.pdfIn PDF document text
    • https://ssvacancy.com/ckfinder/userfiles/files/kipatimitunusajud.pdfIn PDF document text
    • http://autoneza.cz/UserFiles/File/60216636404.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/c460a116e05c284ec60eb2ec5a562b71/sadigomuruk.pdfIn PDF document text
    • https://www.ferienhof-schneider.de/wp-content/plugins/formcraft/file-upload/server/content/files/16139b50c6a0da---sosexajasavijesomufetuj.pdfIn PDF document text
    • https://basundharamart.com/userfiles/file/gikesepixunavi.pdfIn PDF document text
    • https://medicentrumnz.eu/medicentrum/files/file/wuliwubavuzozaxanibuku.pdfIn PDF document text
    • http://klick-tipp.at/ckfinder/userfiles/publics/files/17009858961.pdfIn PDF document text
    • https://frennphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613bcaed23b09---66559766687.pdfIn PDF document text
    • http://ge-mak.com/files/77384794734.pdfIn PDF document text
    • http://biemmecommerciale.eu/userfiles/files/kotakuboluxokikujipototen.pdfIn PDF document text
    • http://zjleiou.com/images/upload/File/zematubutelenukufogilifi.pdfIn PDF document text
    • https://exam10.menapoint.com/app/webroot/upload/files/xivozo.pdfIn PDF document text
    • http://lightofislamonair.org/uploads/files/37869527963.pdfIn PDF document text
    • http://tomasmrazek.cz/userfiles/file/80230453077.pdfIn PDF document text
    • http://buren-kompanie.de/userfiles/files/zojapajafutazalavibebifal.pdfIn PDF document text
    • https://vnmmalta.com/userfiles/file/10321937505.pdfIn PDF document text
    • https://mtestbd.com/assets/uploads/files/53166035356.pdfIn PDF document text
    • http://www.jindatunnel.com/up_files/file/67029976861.pdfIn PDF document text
    • https://sportyou.fr/ckfinder/userfiles/files/bozobexizijebovo.pdfIn PDF document text
    • http://security-m.jp/tool/images/file/15722470608.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/GLLx1DTH0VQ/uplcv?utm_term=example+of+discrete+variable+in+real+lifePDF 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_off0000b555.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB555 11072 bytes
SHA-256: f2fc43a93d61d37b8dcb2a237d390caf9a4c143a4fa80f85ff8add0c34634f9e
font_01_sfnt_off0000ceee.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCEEE 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e700.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE700 16320 bytes
SHA-256: 6b5d5472252db7681925c60e38a8b1f788004e3ace635e16cacca835d822f40e