Malicious PDF — malware analysis report

Static analysis result for SHA-256 a21609c8ec361c43…

MALICIOUS

PDF

108.7 KB Created: 2021-07-25 14:21:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 5a0d7ff2b115743bc7bcb911c8811fa8 SHA-1: 2437790eb374c1ea03918fa114c6b2656b5d3e74 SHA-256: a21609c8ec361c4302603881b2e9c829ebf05dc92bde1bfb969eb884a6dd25d1
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, containing numerous URLs pointing to compromised WordPress upload storage and other disposable hosting sites. The primary purpose appears to be redirecting users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9916

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://chambredhotes-savoie.com/ckfinder/userfiles/files/19174472027.pdf In PDF document text
    • http://www.britocunhaadvocacia.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/1609288eb9f906---55109503073.pdfIn PDF document text
    • https://churchosonline.com/wp-content/plugins/super-forms/uploads/php/files/99e10af098ba3b5dc4a13606a2504427/wenamowanuxadexozuwotu.pdfIn PDF document text
    • http://www.sun-green.eu/ckfinder/userfiles/files/xegalabasakunezijetawi.pdfIn PDF document text
    • http://au-zlato.sk/upload/files/20811165014.pdfIn PDF document text
    • https://vienhung.com/webroot/img/files/sasufoladuxama.pdfIn PDF document text
    • http://otvorene-srdce.sk/userfiles/file/jeduv.pdfIn PDF document text
    • http://www.infranetltd.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f5d146449f0---42614642156.pdfIn PDF document text
    • http://xn--939a66v0zjo3bcvdmrp.com/data/ckfinder/files/lizuvavizexufibeg.pdfIn PDF document text
    • http://dmn.ca/wp-content/plugins/formcraft/file-upload/server/content/files/16076d3081e532---tedonupenuxumiselogof.pdfIn PDF document text
    • https://www.ideakliniksisli.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607b2f919a8df---54532039084.pdfIn PDF document text
    • https://aravlicraft.com/cmsCart//upload/file/81347912494.pdfIn PDF document text
    • https://bouwservicewinthagen.nl/userfiles/image/file/41201753022.pdfIn PDF document text
    • http://gdaniec.com/upload/files/pagisukodido.pdfIn PDF document text
    • http://internationalnetworksolutions.net/files/In PDF document text
    • http://irmascaritasdejesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160959f76e941f---37235823529.pdfIn PDF document text
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/160943f58960b8---povakafajazebevu.pdfIn PDF document text
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160970bdfb24e1---6631665139.pdfIn PDF document text
    • http://www.loockuniformes.com.br/home/wp-content/plugins/formcraft/file-upload/server/content/files/160e52bf316557---94666450511.pdfIn PDF document text
    • https://brokenspoke.com/wp-content/plugins/super-forms/uploads/php/files/c494639c1bec65a9d6ce95f97f7115f6/bozerorizovebejibo.pdfIn PDF document text
    • https://tehnol.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1609d65995e089---30595236291.pdfIn PDF document text
    • https://questyme.com/userfiles/file/44709093125.pdfIn PDF document text
    • http://ersatzmonitor.de/userfiles/file/simogirotikovokukitin.pdfIn PDF document text
    • https://irisapp.cn/uploadfiles/fckeditor/20210624/file/16244752523544.pdfIn PDF document text
    • http://chatfieldfarms101.com/userimages/zobalorim.pdfIn PDF document text
    • http://classicalgardenfountains.com/uplds/file/65612471740.pdfIn PDF document text
    • http://suportti.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608b5b84d8610---36217781987.pdfIn PDF document text
    • http://rajeshjshahani.com/clients/d/de/defaee86e9f1fedea086b53a5072ac2c/File/kabobatar.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/DOqCt-cVA4I/uplcv?utm_term=la+baleine+blanche+full+moviePDF 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_off00014534.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14534 19392 bytes
SHA-256: f5f4dbfe367b927a5169db115d4d9978e81a89f660bc8d9e7b5275f19a845194
font_01_sfnt_off000174f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x174F8 10500 bytes
SHA-256: dfebddb0f01513939e2a1ce7b5fc40101936662c26f8143427c3381b4c13e9ab
font_02_sfnt_off00018ca5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x18CA5 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1