Malicious PDF — malware analysis report

Static analysis result for SHA-256 c1e7cd5635759988…

MALICIOUS

PDF

75.6 KB Created: 2021-06-20 16:46:43 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-29
MD5: 42b852e213421ed71f41223c3e99cf7e SHA-1: e6a50fd146aee91d22b87db9655e6dde5a336beb SHA-256: c1e7cd563575998817be0dadd2fb1d7e059f1b03aecee73bec76b85c332a938d
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs, many pointing to compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to phish or redirect users to malicious content. The presence of multiple compromised CMS upload links suggests a pattern of hosting malicious files on vulnerable websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9998

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://unosms.us/userfiles/file/2414848451.pdf In PDF document text
    • https://astek-telem.fr/userfiles/file/60469350028.pdfIn PDF document text
    • http://mgmkt.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a966e95057d---43677988248.pdfIn PDF document text
    • https://www.jahnigterbraak.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1609ef21178344---26941804162.pdfIn PDF document text
    • https://andrejc.si/files/file/63040905397.pdfIn PDF document text
    • http://www.hollyskauaicondo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a230b241196---sipabebezoginufu.pdfIn PDF document text
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/1607af2398fb7e---nijopuxemasekomomig.pdfIn PDF document text
    • https://unitedcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abf1577f67a---65152022408.pdfIn PDF document text
    • https://ildiko-szepsegszalon.hu/userfiles/file/66570893466.pdfIn PDF document text
    • http://lube-stc.com/ckfinder/userfiles/files/ronurifu.pdfIn PDF document text
    • https://cmsschoolkg.org/userfiles/file/wefikujejumotuzuzinoteri.pdfIn PDF document text
    • http://ajivikafinance.com/userfiles/file/nexovimowixebuniguz.pdfIn PDF document text
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1609ab16ad4ac3---8840077364.pdfIn PDF document text
    • http://barrarioservicos.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160c869f849d88---wedefexi.pdfIn PDF document text
    • http://amandatravel.com/userfiles/file/mipogepapurij.pdfIn PDF document text
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/160b206f096147---jafuvuwejog.pdfIn PDF document text
    • http://yuanyoujie.vip/userfiles/file/62912315404.pdfIn PDF document text
    • https://alignerco.com/wp-content/plugins/super-forms/uploads/php/files/8f5cc231d2bb95fe101fedc0740e9c59/91195470506.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/1KS0DP0cxss/uplcv?utm_term=general+knowledge+geography+quizPDF 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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e854.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE854 5508 bytes
SHA-256: 6bff2994640b41f01e8b44583ef390270fd2db9263a3f467f88c7c8829477779
font_01_sfnt_off0000fb20.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFB20 11276 bytes
SHA-256: 4ab67878a5dc3f7f78a497d60984d1596a1a83a3a9e595ed2afd4fa38a49f710