Malicious PDF — malware analysis report

Static analysis result for SHA-256 55c0f09dce841b31…

MALICIOUS

PDF

81.0 KB Created: 2021-09-17 13:38:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ee10f46268d69477fbbfb3da6df6a4df SHA-1: 8ac5c2354b8cef0ed65f995b16d5cd8c09dfe5a0 SHA-256: 55c0f09dce841b315b5dde8392169c5a1099766f93baff9088aa6c422520c4db
156 Risk Score

Malware Insights

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

The PDF file was flagged by ClamAV and an ML classifier as malicious, indicating a high likelihood of malicious intent. Heuristics identified it as a link farm, with several URLs pointing to compromised CMS upload directories. The document body is heavily obfuscated, preventing analysis of its specific content, but the presence of numerous links suggests a phishing or redirection scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9911

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://www.gyndoktors.de/ckfinder/userfiles/files/92983311658.pdf
    • http://fusheng-vietnam.vn/admin/webroot/upload/image/files/88634378775.pdf
    • https://vnycc.com/userfiles/file/74388377435.pdf
    • http://villapellegrino.it/userfiles/files/9144007745.pdf
    • http://charugarware.com/DEVELOPMENT/charu_garware/uploaded/userfiles/file/rajetupemi.pdf
    • http://champagne-marc-chauvet.com/images/files/vikemubitafarutapu.pdf
    • http://medicalproduct.hu/images/files/rasumafefesoretikubunojib.pdf
    • http://szermgrt.hu/uploads/ckfinder/userfiles/files/gepidopiduvudel.pdf
    • http://www.yourhealthyourchoice.org/wp-content/plugins/formcraft/file-upload/server/content/files/16135d253aea78---30145169198.pdf
    • https://secolink.sk/userfiles/file/60185432504.pdf
    • https://mchs.kz/userfiles/File/roluxazi.pdf
    • http://alimentosldm.com/userfiles/file/56159638581.pdf
    • https://www.playitdirect.ca/ckfinder/uploadfiles/files/vupov.pdf
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1613c0e05bb63c---16508918134.pdf
    • http://duhochoangthanh.com/upload/files/vujetevapovusedew.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135889099a0a---gadif.pdf
    • https://asiatravel.kg/wp-content/plugins/super-forms/uploads/php/files/293d23e7f3a40d0d5dba3384c3d2d2d6/mojex.pdf
    • https://stephankeppel.com/userfiles/file/wafidegopi.pdf
    • https://plewmal-d.com/Uploads/files/889003741.pdf
    • https://netiko.ge/img/Data/file/gixilali.pdf
    • https://purevdavaa.mn/uploads/ckfinder/files/kexupebazizafu.pdf
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/7c730f725227a6d6e48ae8de73cdde62/bawilusesu.pdf
    • http://dieutrimun.myphamkangnam.vn/webroot/img/files/rixilirafexu.pdf
    • http://xn----8sbfhu6ab4bqv.xn--p1ai/userfiles/file/joxopanojebisafenu.pdf
    • http://vers-ma.de/userfiles/file/sazexupekifak.pdf
    • http://steakpluspizza.us/userfiles/file/10976059453.pdf
    • https://12shio1.com/contents/files/80700749716.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/A3Ryygt5BCM/uplcv?utm_term=rate+of+change+of+velocity+is
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d4ae.bin
71eb62b9047b2b7019aae7fac1061dc1bdd4b900a5225f326035d913be7155e9
pdf-font-stream PDF embedded font (sfnt) at offset 0xD4AE 18496 bytes
font_01_sfnt_off0001052a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1052A 16792 bytes
font_02_sfnt_off00011d41.bin
086acbf5d0e7398718a00c463882b476fd0920cd483ad4e9b597e851d42358af
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D41 10740 bytes