Malicious PDF — malware analysis report

Static analysis result for SHA-256 b519a2bc42072e24…

MALICIOUS

PDF

86.7 KB Created: 2021-06-25 17:55:02 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3358e5830c8f7a3770947f5e879892ae SHA-1: 2cba7d106f1c7168e96e8ee0e50dea38bbb6f6b0 SHA-256: b519a2bc42072e24c45bf75f838572fd28c93640a3da697807e7102d7eb85cf8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to distribute malicious content or phish users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely related to phishing or malware delivery via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9972

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://krisoc.ru/uplcv?utm_term=passing+out+episodes
    • http://xn--80aadq3ae7aa5k.xn--p1ai/upload/file/45717919272.pdf
    • http://7tec.ru/userfiles/files/pitopagovomupizupujep.pdf
    • http://www.ausafrica.co.za/wp-content/plugins/formcraft/file-upload/server/content/files/16079d0424ce0e---98552499657.pdf
    • http://stasta.com/userfiles/file/66713864038.pdf
    • http://envigest.cz/upload/file/pudixiwesuv.pdf
    • https://maydongy.com/wp-content/plugins/super-forms/uploads/php/files/o7jg84ea9q99d0bl4lp5nonml1/57746845044.pdf
    • https://balbok.net/admin/ckfinder/userfiles/files/61458318642.pdf
    • http://allasclub.com/campannas/file/jinevikuzurewalomibog.pdf
    • https://3dreamstudios.com/wp-content/plugins/super-forms/uploads/php/files/311d0f1a1f30c424a1d20d2df455644b/tufoke.pdf
    • http://www.verneteco.com/ckfinder/userfiles/files/33279111301.pdf
    • http://ednak.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2d0acc1edb---judibet.pdf
    • https://lakecountyoralsurgery.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c2ee39093e4---81189488026.pdf
    • https://www.ediliziaindustriale.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bab54430ebf---89684851478.pdf
    • http://anupbolivia.com/images/files/69611050557.pdf
    • http://www.cuerpomenteyespiritu.es/wp-content/plugins/formcraft/file-upload/server/content/files/1607783e17629a---58685014348.pdf
    • https://www.plsok.com/wp-content/plugins/super-forms/uploads/php/files/ca457f28467f11c995d7e2a6de8e2b62/89428096384.pdf
    • http://slsnn.ru/content/file/buvilabosutaj.pdf
    • https://www.caesarstravel.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a72c81880c---51563256099.pdf
    • http://www.grupohk.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a7d9d94d35e---90744690912.pdf
    • http://www.vitrierbxl.be/wp-content/plugins/formcraft/file-upload/server/content/files/1607433a219c61---pojuragawejefirubuzizux.pdf
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/20cng3ap78hnfgjtvb1krflv2g/wiwuvojevefepaxabaribuda.pdf
    • 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_off0000f15b.bin
a725982fdd40ceaf8ee04ec3a38c2d1486573985c7629de0a1e03f3e777aa2c3
pdf-font-stream PDF embedded font (sfnt) at offset 0xF15B 10524 bytes
font_01_sfnt_off0001093c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1093C 16792 bytes
font_02_sfnt_off0001214e.bin
ff46a3b22bd4940f83eb78c988f127a23c381686b2bd8d408b467d956198a5b6
pdf-font-stream PDF embedded font (sfnt) at offset 0x1214E 16632 bytes