Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8aa3d6871b4ad13…

MALICIOUS

PDF

92.9 KB Created: 2021-07-08 04:11:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: f8759cb7e7df161b68148616a8336807 SHA-1: af6d791b5c4b363ae5d064acf314ccac05a9639f SHA-256: f8aa3d6871b4ad13e5a18a7efd628fdd0e2e4ba317dfa4d7dcb855e661c06fb9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous links, many pointing to compromised CMS upload directories, suggesting a link farm designed to redirect users to potentially malicious content. The ClamAV detection and ML classifier strongly indicate malicious intent, likely phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9935

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 http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e355efc9cd5---84479252060.pdf In PDF document text
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/9893fb3e96b3c96590f10c9c2d414374/vixopu.pdfIn PDF document text
    • http://innovatepc.com/userfiles/file/51874908204.pdfIn PDF document text
    • https://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/a6cff685a3bfd68cb908cdf6c9a2404f/mepowujagafafiwa.pdfIn PDF document text
    • http://travellightnepal.com/userfiles/file/39808387690.pdfIn PDF document text
    • https://www.denisonlandscaping.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c17578d2a76---tizufasikoxujovarewuduju.pdfIn PDF document text
    • https://nuevocoach.co.uk/wp-content/plugins/super-forms/uploads/php/files/3180b41c80b5dbf97ca2200ee6d71460/20591328461.pdfIn PDF document text
    • http://megalaserasia.com/upload///kudorobopebaseweke.pdfIn PDF document text
    • http://matstravel.ru/userfiles/file/punuwaku.pdfIn PDF document text
    • http://www.ashtralmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b7fc76f2d13---refawidazesuvuwobigadu.pdfIn PDF document text
    • https://law.myvzl.com/wp-content/plugins/super-forms/uploads/php/files/78jdmgqch0jdrsfjoc74muksq8/damoji.pdfIn PDF document text
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/3a6f860390f4e2b20faf6c2c540caad4/figopifajokudov.pdfIn PDF document text
    • http://www.timtransportes.com/home/wp-content/plugins/formcraft/file-upload/server/content/files/160856e3da2425---salunixamulizejoworum.pdfIn PDF document text
    • https://ventana-sur.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071867717b03.pdfIn PDF document text
    • http://www.sunarmisir.com.tr/wp-content/plugins/super-forms/uploads/php/files/l30cuvcjofo2hkan68vb8ehpk0/nerubuvapufalogizoj.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/160b66853c1f56---88959427943.pdfIn PDF document text
    • http://studiolegaletrotta.eu/userfiles/files/99496943650.pdfIn PDF document text
    • http://omni-links.com/58915380420.pdfIn PDF document text
    • https://excore.hu/ckfinder/userfiles/files/mosinosobofimamoli.pdfIn PDF document text
    • http://kusadasidentalclinic.com/img/userfiles/files/dafafonasiwirudewib.pdfIn PDF document text
    • http://asalsold.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fe3d773e5f---6903464132.pdfIn PDF document text
    • https://pabausa.org/wp-content/plugins/formcraft/file-upload/server/content/files/1606d6bc0f30a0---79541186144.pdfIn PDF document text
    • http://europeanprofservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/16075de3a04a01---fulurafesaxov.pdfIn PDF document text
    • https://fitnessrev.net/wp-content/plugins/super-forms/uploads/php/files/j61molfo0mgi9aj53uspkekhp4/28327037972.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=star+constellations+word+search+proPDF 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_off000103e4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x103E4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00011bfb.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11BFB 10772 bytes
SHA-256: 0df7fd8966231273cf6f2769f4c58a6710c707b833079cb4e715307331f367b7
font_02_sfnt_off000134b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x134B9 18540 bytes
SHA-256: 99e97d40eb7c8c146ba3925da1a196a50c7163ab7b5a6f1e7aca5bec1d38e6a8