Malicious PDF — malware analysis report

Static analysis result for SHA-256 f24a51eabd3b1d93…

MALICIOUS

PDF

68.6 KB Created: 2021-09-15 18:56:44 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: d137d21fa2293388fb24beb49fc8ec1c SHA-1: 8beac79164b8c4c6459b08d8d7074a1215334975 SHA-256: f24a51eabd3b1d930aefe2df8a2f29ca6a59b943fbb6c38de628614b0e27fb5e
156 Risk Score

Malware Insights

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

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristic analysis indicates the document functions as a link farm, directing users to multiple external websites, some hosted on compromised CMS uploads. The presence of numerous unknown URLs suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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://aiwcecckolkata.org/FCKeditor/file/wakadelelenedekuz.pdf In PDF document text
    • http://arenda-v-novosibirske.ru/ckfinder/userfiles/files/gagumajotunalure.pdfIn PDF document text
    • http://jmk.kr/ckfinder/userfiles/files/15144250008.pdfIn PDF document text
    • https://gpagroup.in/wp-content/plugins/formcraft/file-upload/server/content/files/16141c4c157e77---49051617389.pdfIn PDF document text
    • https://bahamianbrewery.com/ckfinder/userfiles/files/38250189690.pdfIn PDF document text
    • https://dfa-finanz.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613a6f5b74e5b---43962968316.pdfIn PDF document text
    • https://dptech.vn/uploads/files/zudoxosoxupe.pdfIn PDF document text
    • http://www.enjoyvaltellina.it/admin/ckfinder/userfiles/files/89450069495.pdfIn PDF document text
    • https://inprovitargentina.com/ckfinder/userfiles/files/53742766409.pdfIn PDF document text
    • http://hanshintech.net/data/file/winimejotez.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1613388906d68e---25086164686.pdfIn PDF document text
    • http://marisqueandopremios.com/campannas/file/zulude.pdfIn PDF document text
    • https://adikmanis.com/contents/files/vofitorujuwirewum.pdfIn PDF document text
    • http://ecofincas.net/ckfinder/userfiles/files/kijusimewusixonamafupege.pdfIn PDF document text
    • http://mastrodibaglio.it/userfiles/files/10013924488.pdfIn PDF document text
    • http://tce.vn/imagesflashupload/file/59960947053.pdfIn PDF document text
    • http://qtjdb.com/UploadFile/2021/09/12/file/20210912_041501_122.pdfIn PDF document text
    • http://www.bandungmesin.com/file/64869788398.pdfIn PDF document text
    • http://ablerexthailand.com/userfiles/files/pikizobetuwumobabev.pdfIn PDF document text
    • http://projecthouse.bg/uploads/CKfinder/files/8934299779.pdfIn PDF document text
    • http://xszhuhai.com/uploadfiles/files/titisidizemososudadoverix.pdfIn PDF document text
    • https://holcom-wd.holcom.vn/webroot/img/files/jikidogapizuf.pdfIn PDF document text
    • https://himalayanthailand.com/image/upload/File/togatur.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=android+11+download+pcPDF 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_off0000b21a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB21A 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca2c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA2C 14412 bytes
SHA-256: 65af9f7642a3dba189ac54fe0f2737190b28cb466983f2137ac3ea3e701a81d9
font_02_sfnt_off0000ed9d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED9D 10228 bytes
SHA-256: 6936c04f8b37db7556351bffe59b626c6bf696a4437e19ba33c7be101af351ea