Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b4cfd96c17ef853…

MALICIOUS

PDF

74.9 KB Created: 2021-09-13 15:32:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 584226cd4b43f98f627a6616dabc84a5 SHA-1: d492f410e2f5b70b0577b151d546ddd96591948f SHA-256: 4b4cfd96c17ef853db17dbb8c6f28560c27f7f391134895915dc020c1c476f19
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF file flagged by ML classifiers and ClamAV as malicious. It contains embedded JavaScript and numerous external URIs, many of which point to compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution scheme. The embedded JavaScript likely facilitates the redirection to these malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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
  • 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.
  • 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.
  • 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://sbkf.org/files/files/bexoza.pdf In PDF document text
    • http://shangrilatheshow.com/ckfinder/userfiles/files/57175321752.pdfIn PDF document text
    • http://sententtech.com/file_media/file_image/file/85643152495.pdfIn PDF document text
    • https://cbolean.com/wp-content/plugins/super-forms/uploads/php/files/cf1e7ac5b491621b91d5804d03a05a10/50773541117.pdfIn PDF document text
    • http://i-physiology.ru/upload/tafabosud.pdfIn PDF document text
    • https://n-v-v.dk/userfiles/file/77356775868.pdfIn PDF document text
    • http://2safe4u.cz/UserFiles/File/tudixonezonikup.pdfIn PDF document text
    • https://havadisname.com/upload/ckfinder/files/biwebexonix.pdfIn PDF document text
    • http://www.vivelamusica.es/wp-content/plugins/formcraft/file-upload/server/content/files/16135c721f2d62---wulekakejakiruseboke.pdfIn PDF document text
    • http://avon-bratislava.com/files/files/buvuxapoferiwojofa.pdfIn PDF document text
    • https://highfieldhousehotel.net/nbloom/fckuploads/file/xedezanep.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b4fb415ee5---demuxerisemofonojofox.pdfIn PDF document text
    • https://www.vasutaszeneiskola.hu/ckfinder/userfiles/files/17912251949.pdfIn PDF document text
    • http://teamhead.net/userfiles/file/rukazumuvawo.pdfIn PDF document text
    • http://saktigroup.in/uploads/14922089772.pdfIn PDF document text
    • http://www.palmettoexpresslanes.com/system/js/back/ckfinder/userfiles/files/32804119384.pdfIn PDF document text
    • https://magiccat.pro/ckfinder/userfiles/files/45508054520.pdfIn PDF document text
    • http://lor-rostov.su/userfiles/files/dolinulalotuvas.pdfIn PDF document text
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f27b00c431---46421987300.pdfIn PDF document text
    • http://www.ks-klinika.ru/ckfinder/userfiles/files/rekurogawarasikogene.pdfIn PDF document text
    • https://ncsccalgary.com/userfiles/files/91946407269.pdfIn PDF document text
    • http://htk2.altrodesign.eu/ckfinder/userfiles/files/pomalopimewobafe.pdfIn PDF document text
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/161352cbf26ff0---zufibuvoluw.pdfIn PDF document text
    • http://congtrinhnhaviet.vn/upload/files/75364465382.pdfIn PDF document text
    • http://makaeximworld.com/wp-content/plugins/formcraft/file-upload/server/content/files/16135e72370b39---22419115615.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/YTWXjIUwRh0/uplcv?utm_term=nba+2k20+mycareer+locker+codes+ps4PDF 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_off0000bbf4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBBF4 18680 bytes
SHA-256: 8ae913e8eeb86eec4227015bddb488843a377405e10a58da689c32263649a9b4
font_01_sfnt_off0000ec8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEC8D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000104a4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x104A4 11024 bytes
SHA-256: 0cfdd78be810507a33af36c603246e2b42ea4e7219db08aee6012b1b878a5217