Malicious PDF — malware analysis report

Static analysis result for SHA-256 187d177f363123b8…

MALICIOUS

PDF

80.4 KB Created: 2021-09-16 09:05:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 09a160dc0a314bec7cb9261dcbc38d59 SHA-1: 4f3a24de336f89d3f45d59a049aba455bbbe11c1 SHA-256: 187d177f363123b853e2260367145f30d670eec82621a721e9a62137ded09079
156 Risk Score

Malware Insights

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

The PDF contains numerous links to external websites, many of which are hosted on disposable domains or compromised CMS uploads, indicating a link farm designed to distribute malicious content. ClamAV detection and ML classification strongly suggest malicious intent, likely phishing or malware delivery. The presence of multiple PDF link farm heuristics further supports this conclusion.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://synerhu.ru/uplcv?utm_term=exciting+words+that+start+with+m
    • http://harekatmemuru.com/images/Media/files/mugutelajusodegovazudob.pdf
    • https://artedeeducar.com.br/ckfinder/userfiles/files/bebudezonit.pdf
    • https://afritransport.com/app/webroot/files/file/46069066885.pdf
    • https://christianboudreau.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a2e984d1b0---gafogonuvu.pdf
    • http://greenhere.cn/upload/ckimg/files/202109051718105985.pdf
    • https://goldenlinejsc.com/userfiles/file/54101139093.pdf
    • http://ng-sons.com/userfiles/file/96011189670.pdf
    • https://egokituz.eus/files/galeria/files/1265053942.pdf
    • https://www.tcf.gov.tr/ckfinder/userfiles/files/47580457863.pdf
    • http://kleinschaden.expert/userfiles/file/63010592106.pdf
    • http://111-orte.com/testarea/cwsCMSlight/media/files/4986116312.pdf
    • http://adasbruiloften.nl/userfiles/file/83935385738.pdf
    • http://perfect-gallery.com/userfiles/file/kinax.pdf
    • http://amphorabeautyclub.com/campannas/file/zifiz.pdf
    • https://www.swx.global/wp-content/plugins/super-forms/uploads/php/files/1f14c3b9464720d4e34ed112a6c9e306/kosefonopuxuvevuluzugup.pdf
    • http://sheilahancock.net/blogfck/file/rovipuvij.pdf
    • http://vektor-bezpeki.com/userfiles/files/12342070643.pdf
    • http://psystems.gr/Administrator/uploads/userpics/OutPostImages/files/25726525746.pdf
    • http://groupkaishan.com/d/files/20417365377.pdf
    • https://dukupahit.com/contents/files/8253413142.pdf
    • http://leadershipcareer.kr/fckeditor/_upload/file/bexebew.pdf
    • https://pilot-nav.com/ckfinder/userfiles/files/zaxod.pdf
    • http://kioskcondoweb.wpengine.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613afc10513aa---sagok.pdf
    • http://mustang.tom.ru/jsplugins/ckfinder/userfiles/files/kovalibenaguxikubiduto.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_off0000d6a3.bin
5dcb4b43f07307c5d0e892dfc1e8d5863c149b0dd18871cc307a51545c0a79cb
pdf-font-stream PDF embedded font (sfnt) at offset 0xD6A3 10808 bytes
font_01_sfnt_off0000ef3d.bin
fa9e1f4d83182b0c1d430a32046e54b4114f7194ed1d0811ae333b80d4af55fc
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF3D 17152 bytes
font_02_sfnt_off00011b9e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B9E 16792 bytes