Malicious PDF — malware analysis report

Static analysis result for SHA-256 57688e056620b8a4…

MALICIOUS

PDF

81.8 KB Created: 2021-09-02 11:49:27 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c1e40d63ab3c4b3ed9fdab59f2be17e8 SHA-1: a6279dc42242f7323e1802d7a7ab3260d82139b7 SHA-256: 57688e056620b8a48775888d86986c0f37fec748f422fe71ab3c285de46e3ad8
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF file was flagged by ML classifiers and ClamAV as malicious. Heuristics indicate it functions as a link farm, directing users to multiple external URLs, some hosted on compromised CMS platforms or disposable domains. These links are likely intended to lead users to phishing sites or download further malicious content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

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://queure.ru/uplcv?utm_term=tanix+tx6+user+manual
    • https://kisikana.hr/UserFiles/files/bebeme.pdf
    • http://medicaldistri.com/ckfinder_files/files/dawib.pdf
    • http://thanhlamresort.vn/wp-content/plugins/formcraft/file-upload/server/content/files/160cab1b9e4d81---nirakuxipolojilonanubepu.pdf
    • http://surtek.biz/image/files/20150119_013044.pdf
    • https://mimpiindah88.com/contents/files/bamutasanofojumikag.pdf
    • https://motodubai.com/uploaded_images/files/50769492979.pdf
    • https://ruxthai-guesthouse-chiangmai.com/ckfinder/userfiles/files/xovejemosibegebexovu.pdf
    • https://clickkedai.com/userfiles/file/tutoduriwomuzuja.pdf
    • http://dermalab.pl/userfiles/file/feneluwibigimabe.pdf
    • https://warsztatgdynia.pl/app/webroot/media/files/18682963897.pdf
    • https://bataretak.com/img/files/file/sojikokamanosuwavutuwimap.pdf
    • https://er-cardiff.com/eurostyl/photos/file/soxebaziriripakeki.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160712fee4f5ce---77338379698.pdf
    • http://www.insurancedirectcanada.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160b8a7c69f35a---18116536896.pdf
    • http://accessprecision.com/userfiles/file/vamonudafegutigulapuje.pdf
    • http://seanmore.com/userData/board/file/madivudodipitam.pdf
    • http://jfhconsultancy.nl/userfiles/files/19530335725.pdf
    • https://expungemyrecordnj.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609607d0cbfba---21363250821.pdf
    • http://lovec.bg/root/ckfinder/userfiles/files/20844748751.pdf
    • http://marcus-1.com/FileData/ckfinder/files/20210614_FCB679E5ACFFFD83.pdf
    • http://dunajecbiala.pl/upload/File/vapojopofenuvebuwetil.pdf
    • https://zoomkish.com/basefile/zoomkishcom/files/farejiwevinemolefuja.pdf
    • http://feach.ie/images/uploads/file/75413580710.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_off0000db88.bin
acb260cb4fc6f00997ded4b7417da0079621eda0eb3aadc2d9de9851965d8767
pdf-font-stream PDF embedded font (sfnt) at offset 0xDB88 17884 bytes
font_01_sfnt_off000109f5.bin
e8fdb5bd071c4ed7eae07a41da1376f57fe0f7ca751e5c864d9b572fac64b93a
pdf-font-stream PDF embedded font (sfnt) at offset 0x109F5 10480 bytes
font_02_sfnt_off000121da.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x121DA 16792 bytes