Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd65a8eab23ac901…

MALICIOUS

PDF

89.2 KB Created: 2021-09-13 06:20:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-11
MD5: b3a72a01378ebb9b07b1d2b93b0bdfd3 SHA-1: 80569be4dd72cb2b4feaf20d3aa27a08545c99c6 SHA-256: dd65a8eab23ac9017baea27efeb402ca0c0424b44536daa1b462790394b158ae
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is identified as malicious by ClamAV and an ML classifier, with heuristics indicating embedded JavaScript and a link farm pointing to compromised WordPress sites. The embedded JavaScript likely facilitates the redirection to malicious URLs, which are part of a link farm designed to obscure the final destination. This suggests an attempt to lure users to potentially malicious content or phishing sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://gtsonline.nl/wp-content/plugins/super-forms/uploads/php/files/fv6iiohjvjivrce41vkejlcr52/55382154184.pdf In PDF document text
    • https://curvy.tw/upload/files/tobefuvusamugul.pdfIn PDF document text
    • http://nnk.gr/wp-content/plugins/formcraft/file-upload/server/content/files/16137510e13ed7---28352299163.pdfIn PDF document text
    • https://bushregenerators.com/userfiles/files/56779926890.pdfIn PDF document text
    • https://alkoplast.rs/files/70722713153.pdfIn PDF document text
    • http://angel-conference.org/upload_fck/file/2021-9-4/20210904191545263708.pdfIn PDF document text
    • http://locke-3c.tw/uploads/files/202109112020572935.pdfIn PDF document text
    • http://www.ramseier-appenzell.ch/elrada/js/ckfinder/userfiles/files/nudapitanipevovupowomud.pdfIn PDF document text
    • http://st-ark.it/userfiles/files/40644491538.pdfIn PDF document text
    • https://vwb.mrv-educationservices.com/content_file/files/fegejukizakekavulu.pdfIn PDF document text
    • https://newat.ru/wp-content/plugins/super-forms/uploads/php/files/3487f54acdde016bf8686127e7e3527d/zojekesopuretofunuledunex.pdfIn PDF document text
    • https://reclamesticker.nl/images/uploads/file/In PDF document text
    • http://villaturri.it/wp-content/plugins/formcraft/file-upload/server/content/files/16134025c8b04a---26331223082.pdfIn PDF document text
    • https://parquesanalbertohurtado.cl/ckfinder/userfiles/files/24924365118.pdfIn PDF document text
    • https://visualmotion.nl/uploads/file/69937163291.pdfIn PDF document text
    • http://tnshoppingbag.com/upfiles/file/62644847821.pdfIn PDF document text
    • http://ues-rb.ru/themes/ues-rb.ru/files/fixawarotizijugafetodi.pdfIn PDF document text
    • https://netcsemege.elelmiszer-hazhozszallitas.hu/ckfinder/userfiles/files/14802025894.pdfIn PDF document text
    • http://tl-maskinfabrik.dk/userfiles/file/93067074905.pdfIn PDF document text
    • http://rusiuojigalvoji.lt/wp-content/plugins/formcraft/file-upload/server/content/files/1613cdfdaba20c---66567782842.pdfIn PDF document text
    • http://mirutte.com/newsfiles/files/dofopusiwiv.pdfIn PDF document text
    • http://aqs-group.it/userfiles/files/95116685946.pdfIn PDF document text
    • http://fabtur.ru/upload/files/31188459188.pdfIn PDF document text
    • http://yourmoneyyourbank.com/uploads/File/lotukevenafotovag.pdfIn PDF document text
    • http://fabtur.ru/upload/files/wutaxisetoromigabimej.pdfIn PDF document text
    • https://pmms-online.com/assets/file/90510629897.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=best+choices+games+for+androidPDF 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_off0000fa85.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFA85 10928 bytes
SHA-256: 33c953dcfdd09e89bec13457dfcd05106393c335bac3b732e8778bad6e5d26fc
font_01_sfnt_off00011384.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11384 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012b96.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B96 16760 bytes
SHA-256: 5485efaeae0b29972830919c5b1fc263a9c3d13d169c4916b0254b7b45cc562f