Malicious PDF — malware analysis report

Static analysis result for SHA-256 40ef8f463cdb2e6c…

MALICIOUS

PDF

83.1 KB Created: 2021-09-09 09:02:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-14
MD5: 32acefebcf9d63b8639d18c150c3bedb SHA-1: 1f0c6407ecd8ec3ca28b5076159a621e73802a16 SHA-256: 40ef8f463cdb2e6c0cd6ea3ef5a18b9c5b74eee17f0afa7ba05337e786a19449
156 Risk Score

Malware Insights

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

The PDF contains a link farm with numerous URLs pointing to potentially compromised or disposable hosting. Heuristics indicate these links are designed to direct users to external sites, with some hosted on known compromised CMS upload storage. The ML classifier and ClamAV detection strongly suggest malicious intent, likely phishing or malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

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://dnsbp.com/all4help/fckuserfiles/file/sidovi.pdf In PDF document text
    • http://dc-3ed4d7413bdb.prshots.de/uploads/userfiles/1630520831/files/vubixum.pdfIn PDF document text
    • http://kaztelcom.kz/ckfinder/userfiles/files/37814574009.pdfIn PDF document text
    • https://minhvuongthuphap.com/upload/ck/files/2385703286.pdfIn PDF document text
    • http://agrion.org/upload/fichier/1952885426.pdfIn PDF document text
    • http://bergfin.se/wp-content/plugins/formcraft/file-upload/server/content/files/16136f4791e719---mijipovapusajufejumok.pdfIn PDF document text
    • https://lose-weight.tw/upload/files/58958337548.pdfIn PDF document text
    • https://rrr71.ru/upload_picture/jalebe.pdfIn PDF document text
    • http://www.itidharamshala.in/images/uploads/files/93970540859.pdfIn PDF document text
    • http://autobedrijvenindex.nl/images/uploads/suluxukinuvategasoje.pdfIn PDF document text
    • http://phongthuydotho.vn/upload/files/36953176707.pdfIn PDF document text
    • https://hps-gruppe.com/wp-content/plugins/super-forms/uploads/php/files/bnjbaduvi6o3h7bpc5d9pvq3m8/87820825209.pdfIn PDF document text
    • http://thaihotelsale.com/FileData/ckfinder/files/20210903_FD29B068B32F9F0C.pdfIn PDF document text
    • http://www.hausbaumesse.at/ckfinder/userfiles/files/59747450812.pdfIn PDF document text
    • https://fanaf.org/article_ressources/file/36968390135.pdfIn PDF document text
    • https://searchkar.com/ci/userfiles/files/14722740450.pdfIn PDF document text
    • http://chingyi.tw/userfiles/files/24900834382.pdfIn PDF document text
    • http://architettodrabeni.it/userfiles/files/90127207305.pdfIn PDF document text
    • https://drosamahetta.com/userfiles/file/vuvefewaxa.pdfIn PDF document text
    • http://trumoi-khutrung.com/upload/files/41628879608.pdfIn PDF document text
    • http://refinerlink.com/userfiles/file/wawuxatugam.pdfIn PDF document text
    • http://markjfox.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/54756623353.pdfIn PDF document text
    • https://papiratisk.cz/soubory/87578440464.pdfIn PDF document text
    • https://eduinfinite.com/wp-content/plugins/super-forms/uploads/php/files/d64a5e4bc3080d8c32a1434e7f49b0e6/tesurakosozujexiwimib.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=after+we+collided+watch+online+123moviesPDF 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_off0000ddb0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDB0 17876 bytes
SHA-256: f98026b3680f9276afba359dce02654e6d2b623ecdc62ffb0488ab68b697b557
font_01_sfnt_off00010bf1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10BF1 11220 bytes
SHA-256: 673f5b26186c713cca4686fbbcd4fc8e32dfcd0737a1ae3adea80227bd61cca2
font_02_sfnt_off0001263f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1263F 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1