Malicious PDF — malware analysis report

Static analysis result for SHA-256 aec993a3c1069c29…

MALICIOUS

PDF

84.1 KB Created: 2021-09-10 07:49:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 9a08df9fb314b682bef8071039481242 SHA-1: 3aa142d38c02274dd47afc7357ce4bd50b89db5a SHA-256: aec993a3c1069c29692cce0d491d884abe940bcb009823b81086947dea9bee1a
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by a machine learning classifier and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to various domains, including compromised WordPress sites. The presence of these links suggests an attempt to redirect users to malicious content or phishing pages.

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://www.paseppe.gr/ckfinder/userfiles/files/16449368466.pdf In PDF document text
    • http://unite-chem.cn/upload/files/topidigi.pdfIn PDF document text
    • http://usaoxin.com/userfiles/2021-9/file/61254119723.pdfIn PDF document text
    • https://nam.it/wp-content/plugins/formcraft/file-upload/server/content/files/161323ba19ecdb---funamalezep.pdfIn PDF document text
    • http://reiki-roots.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1612feb8845d04---lepagubef.pdfIn PDF document text
    • https://forssh.com/userfiles/file/bafexebok.pdfIn PDF document text
    • http://www.jokilaaksonratsastajat.fi/file/xexutidefadedurarupub.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613567de27e72---denolemilenepu.pdfIn PDF document text
    • https://cfbadalona.net/ckdata/files/mimexopinasudepajo.pdfIn PDF document text
    • http://salkim.com/userfiles/file/14577605942.pdfIn PDF document text
    • http://laibros.com/ckeditor/userfiles/files/jozovemubabatupasetude.pdfIn PDF document text
    • http://westernmaki.com/uploads/files/kubilono.pdfIn PDF document text
    • http://easternhoteljeju.com/FileData/ckfinder/files/20210901_E37E17558877DDE4.pdfIn PDF document text
    • https://kristaldicarlo.com/userfiles/file/jolijezu.pdfIn PDF document text
    • https://fpcofmacon.com/nbloom/fckuploads/file/gakupadem.pdfIn PDF document text
    • http://nagyberki.hu/sites/default/files/fck_uploads/file/kodidiv.pdfIn PDF document text
    • http://fantalife.nl/userfiles/file/jorekewa.pdfIn PDF document text
    • http://sochi-riba.ru/ckfinder/userfiles/files/zufuvodirozovafunilukaku.pdfIn PDF document text
    • https://cardolf.ro/files/27744028397.pdfIn PDF document text
    • http://meruzhankhachatryan.com/app/webroot/files/file/kaluvurujopuwa.pdfIn PDF document text
    • https://luxurytravel-show.com/wp-content/plugins/super-forms/uploads/php/files/19f9cc1ba192ecd15c351ae368d6b743/medizozudikemapozigusa.pdfIn PDF document text
    • http://www.sg-callenberg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1612f7f9011daf---87138839885.pdfIn PDF document text
    • http://ogcdc.org/uploads/ck_upload/files/kajafigo.pdfIn PDF document text
    • https://soechi.com/userfiles/file/2312844504.pdfIn PDF document text
    • https://adian.eus/files/galeria/files/mebiku.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/Om9ozkHLxGw/uplcv?utm_term=how+to+get+unlimited+money+in+pixel+gun+3dPDF 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_off0000e2d3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE2D3 17844 bytes
SHA-256: 6d9d8e0236df85ca25c800ce9c23cd181013c953589d389375b64772641a64a2
font_01_sfnt_off00011138.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11138 10872 bytes
SHA-256: 28042198d085870a51e56c615d5883e556750758b27fbf21bc39d16b2d973c97
font_02_sfnt_off00012a25.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12A25 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1