Malicious PDF — malware analysis report

Static analysis result for SHA-256 f3eecdf51bd06c53…

MALICIOUS

PDF

76.4 KB Created: 2021-09-14 04:04:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: f7a44517a2c44a17f9b15a155c827dd3 SHA-1: 715ced43448b0c5c410a2abf2d337476a66b0385 SHA-256: f3eecdf51bd06c5305fc1c03577a9a634143a5e0142b529258a5c3170462d7a7
156 Risk Score

Malware Insights

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

The PDF was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with many embedded URLs pointing to potentially compromised or disposable domains. The document body is unreadable binary data, suggesting it's not intended for direct user consumption but rather to host links.

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://boras-sjuharad.boj.se/uploads/userfiles/files/75817016171.pdf In PDF document text
    • https://venusnvs.com/userfiles/file/60135530112.pdfIn PDF document text
    • http://bezagsecurity.cz/userfiles/jowikuvelidopuxuvuvoj.pdfIn PDF document text
    • https://cosmopolitanhotelbg.com/uploads/wysiwyg/files/11969619136.pdfIn PDF document text
    • http://www.commandinglife.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136e946acfdd---37624937270.pdfIn PDF document text
    • https://indiansabroad.uk/userfiles/file/88769796352.pdfIn PDF document text
    • http://fine-trading-knotwork.com/uploads/media/nimusus.pdfIn PDF document text
    • http://vodnik48.ru/content/file/xaxodexu.pdfIn PDF document text
    • http://rivebistro.net/ckfinder/userfiles/files/92076575543.pdfIn PDF document text
    • http://denis-lefebvre-services.com/fichiers/file/61794512005.pdfIn PDF document text
    • http://toyotarent.kr/FileData/ckfinder/files/20210907_9EF4A3237884FA91.pdfIn PDF document text
    • https://aquarell.ro/userfiles/file/83049490005.pdfIn PDF document text
    • https://aquaticlandscape.com/wp-content/plugins/formcraft/file-upload/server/content/files/161302e5306233---lipedivuwavomilatuto.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16137617e52aab---fasud.pdfIn PDF document text
    • http://lexuspolymers.com/assets/ckfinder/userfiles/files/96841554003.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16130cbd3824d6---gavokudubozorunafebofo.pdfIn PDF document text
    • https://simpangkanan.com/contents/files/89000086993.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/s8ram8r80bpiabdonu6cmhpi74/xinileko.pdfIn PDF document text
    • https://motionslam.com/wp-content/plugins/super-forms/uploads/php/files/08fc7bbef7d27e747b2479e02eb23d24/gaxiwosoboponiro.pdfIn PDF document text
    • http://nutronicltd.com/userfiles/file/rewuloxazeroketo.pdfIn PDF document text
    • https://noihoithanhtuan.com/media/ftp/file/14810298705.pdfIn PDF document text
    • http://uni-soar.com/userfiles/file/6559639368.pdfIn PDF document text
    • http://imreelectric.sk/uploads/file/15566046520.pdfIn PDF document text
    • https://shibbirs.com/media/files/tinudanijijemibugogalo.pdfIn PDF document text
    • http://esen-life.com/userfiles/file/dusawu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=meme+live+apkPDF 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_off0000c8b8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8B8 17428 bytes
SHA-256: fcdfeb6e0c35a8f65006e102fa58cc77c265cbd4b7c8e4e300a2fb233dde8f30
font_01_sfnt_off0000f5ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5AE 9972 bytes
SHA-256: 78c996d971476d0e116a00e3ff0057055c5cd8b7ae3f46a355385346b90eccf8
font_02_sfnt_off00010bbb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BBB 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1