Malicious PDF — malware analysis report

Static analysis result for SHA-256 67d45e43b6731102…

MALICIOUS

PDF

88.8 KB Created: 2021-08-02 15:10:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: e23e952ccc9eb29956c732fa5ef53d60 SHA-1: fbb0619ec394475ef70da799468fd4fec7d2eb21 SHA-256: 67d45e43b6731102be6baeb335ec4644af61de2140462b6cba205c3646e5ef54
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as link farms. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or SEO spam. No scripts were extracted, but the document structure itself is the attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 http://ceskylakros.cz/userfiles/file/tawafitud.pdf In PDF document text
    • https://calldidocta.com/wp-content/plugins/super-forms/uploads/php/files/3f4f5e1228f11ab46c50d28e0120c3e7/wamelux.pdfIn PDF document text
    • http://socialbomjesus.org.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b3a2a45d8ed---jolunoma.pdfIn PDF document text
    • http://bruisedreedfoundation.org/clients/4/4d/4d9d7eec3bf3a09fa0457ace138f6a4e/File/19733111696.pdfIn PDF document text
    • https://ferado.vn/userfiles/file/velogokavodito.pdfIn PDF document text
    • https://www.focus.mu/wp-content/plugins/super-forms/uploads/php/files/06fb44839a7ed4e4a6fe7dd3b3e98a15/19770832491.pdfIn PDF document text
    • http://www.publicitymailing.ie/wp-content/plugins/formcraft/file-upload/server/content/files/1609eefc88e9d5---82490367389.pdfIn PDF document text
    • https://okud-istra.hr/userfiles/file/99824724554.pdfIn PDF document text
    • http://dkmmotor.com/files/userfiles/file/wakufuzitugevapujox.pdfIn PDF document text
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/ff8eed89730d447d0d112650525fd1fb/tudosita.pdfIn PDF document text
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16090e1e843744---tugomamazotoxa.pdfIn PDF document text
    • https://eksiliotomotiv.com/upload/ckfinder/files/zibogixami.pdfIn PDF document text
    • https://amthanhanhsangchinhhang.vn/upload/files/tusekogoxefaxuj.pdfIn PDF document text
    • http://wijnhuis-vaessen.nl/site/data/ws/files/78759271833.pdfIn PDF document text
    • https://amenagementsoleil.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094bc8578462---jogaxegolosokovodu.pdfIn PDF document text
    • https://tucsonhomewindowtint.com/wp-content/plugins/super-forms/uploads/php/files/0b699ff988abe5ee496a31bf6305dec6/durube.pdfIn PDF document text
    • http://sibservis.com/ckfinder/userfiles/files/wofojaturefetitugek.pdfIn PDF document text
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160ffd66dacb78---23023173833.pdfIn PDF document text
    • http://tuanlongland.com/upload/files/93947752409.pdfIn PDF document text
    • http://thekitchendesignstudio.org/uploads/files/tegukave.pdfIn PDF document text
    • http://musikpark-live.de/userfiles/file/66049171531.pdfIn PDF document text
    • http://haai.org/upload/file/tedutemetamelenupaju.pdfIn PDF document text
    • http://bilagroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d61e51dd649---kexozonaro.pdfIn PDF document text
    • https://dermatologie-francophone.com/userfiles/file/ketewavologusara.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/160748f7dede76---timelu.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=receta+para+preparar+carne+de+puerco+para+tamalesPDF 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_off0000f4c7.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF4C7 18096 bytes
SHA-256: c17142f1e76b62f990bbbd4ca3604430a79b618fee7005bf75288b384d6f025c
font_01_sfnt_off00012292.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12292 10728 bytes
SHA-256: b5ad8d97bb6973d953564ae025c4008a7843f387aa9fbb90681ca9d1288f6f33
font_02_sfnt_off00013b3b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B3B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1