Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac3ed992e3e8b768…

MALICIOUS

PDF

68.7 KB Created: 2021-09-23 21:34:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: ff0b54b30f8e31e2528afc94e0001fff SHA-1: 4a1d094246133bd134b21b4d6823427dc2069f94 SHA-256: ac3ed992e3e8b768c71d73ab80485256bd46884081bb28b7571b8a30f5da0c33
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious. It contains a link farm with numerous URLs pointing to various domains, some of which are identified as compromised CMS uploads or disposable hosting. The presence of these links suggests an attempt to direct users to download further malicious content or visit phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://le-lemniscus-incandescent.fr/ckeditor/upload/files/solojajixababiwidametoti.pdf In PDF document text
    • https://krzczonowice.pl/gfx/file/redikikesomewolubeturinaw.pdfIn PDF document text
    • https://0900107678.com/upload/file/9037108921.pdfIn PDF document text
    • http://nc2e.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16145ac7c22371---naxebosex.pdfIn PDF document text
    • https://dungcuruamui.com/wp-content/plugins/super-forms/uploads/php/files/ma2gli28b7efb5954q5i4pjrrh/637270344.pdfIn PDF document text
    • http://structurecreative.com/wp-content/plugins/formcraft/file-upload/server/content/files/161371b903946e---piwutijorutemibosim.pdfIn PDF document text
    • https://rosanaalvarracin.com/userfiles/file/60201734142.pdfIn PDF document text
    • http://446888.top/userfiles/file/29834019825.pdfIn PDF document text
    • https://mamadona.ru/ckfinder/userfiles/files/26379321173.pdfIn PDF document text
    • https://nhabe.com.vn/ckfinder/userfiles/files/99494574579.pdfIn PDF document text
    • http://impressivetravelvietnam.com/upload/files/wepesa.pdfIn PDF document text
    • http://www.polni.si/Images/files/virefetuwetegutunurubuj.pdfIn PDF document text
    • http://nhuaduongnhapkhauaz.org/upload/files/69280885313.pdfIn PDF document text
    • http://consol.hu/images/uploadedimages/file/zefezofatizodiwepudim.pdfIn PDF document text
    • http://vietkinggroup.com/uploads/userfiles/file/61134559322.pdfIn PDF document text
    • https://ccveg.org/wp-content/plugins/super-forms/uploads/php/files/vbu6avs90k9gfjkbtte2llj1st/kojijajoxewirefam.pdfIn PDF document text
    • http://inphuduong.vn/upload/files/kitugogibideraligixubo.pdfIn PDF document text
    • http://tcsm62.org/uploads/news/file/24517426024.pdfIn PDF document text
    • http://a-xian-coat.com/uploads/files/202109181158379840.pdfIn PDF document text
    • http://cleversystems.ru/userfiles/file/27779402269.pdfIn PDF document text
    • https://cli-kh.com/uploads/files/202109042043196860.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=quickoffice+for+android+2.3+free+downloadPDF 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_off0000ac0a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xAC0A 16372 bytes
SHA-256: 7cfe3c242be437de37c8100500e7bc524661473601317dd81f43f9709c150a1e
font_01_sfnt_off0000d3e2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD3E2 10896 bytes
SHA-256: ee406a150f62fec999d90e96806c2adabb37f5b34b768559084c6cd2224a8eb7
font_02_sfnt_off0000ed6c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED6C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1