Malicious PDF — malware analysis report

Static analysis result for SHA-256 9df5b3b2134b1858…

MALICIOUS

PDF

98.4 KB Created: 2021-09-21 01:58:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-20
MD5: 3cff1cf78c124d0f0dea2b53e36aa31d SHA-1: cb15c71abd0e85b4c0e6d47b0641c818399a3c81 SHA-256: 9df5b3b2134b1858f093f5dba7bd975c7ee9b761eab50bec2bdd791d01b8ac2b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many hosted on disposable domains or compromised WordPress installations, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to distribute malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9965

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 https://chcial.ru/uplcv?utm_term=dragon+ball+budokai+tenkaichi+3+mobile PDF link annotation
    • http://deurwater.com/wp-content/plugins/formcraft/file-upload/server/content/files/16149070044f15---wepepel.pdfIn PDF document text
    • http://urbanelect.com/userfiles/file/87917459038.pdfIn PDF document text
    • https://tlkingatlan.hu/kepek/other/file/13202899233.pdfIn PDF document text
    • https://qualityroofinnandsuites.com/nbloom/fckuploads/file/dodimalutubivuvam.pdfIn PDF document text
    • http://phutungtdc.com/upload/files/diwokafazibejorexofevi.pdfIn PDF document text
    • http://oldmotorsclub.com/files/file/33710311375.pdfIn PDF document text
    • http://trevelci.ru/ckfinder/userfiles/files/fekofaxarezexev.pdfIn PDF document text
    • https://reifenscho.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e3b2c86553---16364462549.pdfIn PDF document text
    • https://elperrocallejero.info/ckfinder/files/dudabojim.pdfIn PDF document text
    • http://www.petercar0937494634.com/upload/img/files/24287990107.pdfIn PDF document text
    • http://reafamily.lt/ckfinder/userfiles/files/vuvog.pdfIn PDF document text
    • http://jhdjt.com/images/upload/File/77965723138.pdfIn PDF document text
    • http://wakesup.org/userfiles/file/84833888259.pdfIn PDF document text
    • https://zegaoyun.com/calisma2/files/uploads/11036780958.pdfIn PDF document text
    • http://idominjazz.com/fckeditor/userfiles/image/47239514884.pdfIn PDF document text
    • http://thedewakohchang.com/image/upload/File/674522924.pdfIn PDF document text
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148847be9b78---98298256738.pdfIn PDF document text
    • http://esistore.lu/userfiles/file/5849231856.pdfIn PDF document text
    • http://kaies.cn/upfiles/file/57301464072.pdfIn PDF document text
    • http://gibisch.org/files/files/64625443927.pdfIn PDF document text
    • https://windscrm.net/files/file/rilusirikutup.pdfIn PDF document text
    • http://jjmcp.jp/userfiles/Image/file/74413993164.pdfIn PDF document text
    • http://brezov-gaj.si/uporabnik/file/boximuzugujisalogifex.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_off0001159c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1159C 20100 bytes
SHA-256: 2553e806ad088dbaed7aeaa066db017d7ea1d578c9e492b6163d7404f6c94458
font_01_sfnt_off000149e3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x149E3 11156 bytes
SHA-256: 0415ad8d90f4dd5d633fa327974da1b31bb8b11d48406332f2cd794f7a6c6857
font_02_sfnt_off0001638c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1638C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1