Malicious PDF — malware analysis report

Static analysis result for SHA-256 ed551e00354d3b92…

MALICIOUS

PDF

104.5 KB Created: 2021-10-05 09:07:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-25
MD5: 0beea0058518be0b4023576225497517 SHA-1: b5ea29ced6ed5997afd180bbdba954e0301ab6da SHA-256: ed551e00354d3b92a061f905a832611dc1970b0cc37f13749921b4284fb7fd1e
164 Risk Score

Malware Insights

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

This PDF file was flagged as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The embedded JavaScript stream and numerous external URIs, many pointing to compromised CMS uploads and disposable hosting, suggest it functions as a link farm designed to redirect users to malicious sites. The primary purpose appears to be distributing further malware or conducting phishing attacks.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 7

  • 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.
  • 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 https://inwebjor.ru/uplcv?utm_term=spm+occupational+therapy PDF link annotation
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/161410ea0c6fbe---66898522375.pdfIn PDF document text
    • https://www.agro-zavod.ru/app/webroot/js/ckfinder/userfiles/files/28139049191.pdfIn PDF document text
    • http://petraifevronii.ru/ckfinder/userfiles/files/63418162427.pdfIn PDF document text
    • https://ajansnigde.com/resimler/files/nagef.pdfIn PDF document text
    • https://mamalight.org/business_school/uploads/file/50241133478.pdfIn PDF document text
    • https://discovercefalu.it/_data/images/file/52195268227.pdfIn PDF document text
    • https://siyata.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/16154483bd9a6c---judowifapo.pdfIn PDF document text
    • http://wooshin.kr/uploaded/file/127153947161317ebb728cc.pdfIn PDF document text
    • http://unipsyclinic.com/userfiles/file/20211004034822.pdfIn PDF document text
    • http://ajej.pretty-match.com/upload/files/54275930027.pdfIn PDF document text
    • http://bienchidan.org/uploads/files/67713701205.pdfIn PDF document text
    • http://realestatespoznan.com/uploads/gosegapeguxinolojilunuw.pdfIn PDF document text
    • http://xn--h1aeekk.xn--p1ai/files/file/keretixofenamapimezap.pdfIn PDF document text
    • http://hajnysport.cz/FCK_userfiles/file/6148297110.pdfIn PDF document text
    • https://venus-forever.com/image/files/wimowapepet.pdfIn PDF document text
    • http://appartenvue.net/appart/upload/images/vovavuzaxubir.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/42067698986.pdfIn PDF document text
    • https://tekartltd.com/upload/files/39168785818.pdfIn PDF document text
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/18f8ba11efc35b69eea16760296f067e/vifemavugig.pdfIn PDF document text
    • https://ikima.fr/uploads/file/61767206782.pdfIn PDF document text
    • http://abcs.umontreal.ca/upload/files/58624183166.pdfIn PDF document text
    • 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_off00012fd8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12FD8 10760 bytes
SHA-256: 1af6f233bd2a5136ccc507e9a64c220ec7f3deb8d3a97c8eed5881e799df756d
font_01_sfnt_off00014863.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14863 20256 bytes
SHA-256: 5fad3be54ac363259a134ea2f02d61ee03ecfffba7abf983474b36435fd1a042
font_02_sfnt_off00017d18.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17D18 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1