Malicious PDF — malware analysis report

Static analysis result for SHA-256 c71c6cd195411403…

MALICIOUS

PDF

97.3 KB Created: 2021-09-07 08:08:22 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 63f3bed89c980ca35ee1ec98e95c8e63 SHA-1: 05625bbf535bbbb9665dc8daded07c2cca5d0b80 SHA-256: c71c6cd195411403acdd69ba3c38fa6fe0ef992f7e0f49b81bf68adad3550d91
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file contains numerous embedded URLs that point to compromised websites and disposable hosting, indicating a link farm designed to redirect users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9969

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://nomylo.ru/uplcv?utm_term=defence+law+manual+vol+3 PDF link annotation
    • http://uitetenindex.nl/images/uploads/1855488033.pdfIn PDF document text
    • https://asiantms.com/ckfinder/userfiles/files/38355886213.pdfIn PDF document text
    • https://www.marvistasales.com/wp-content/plugins/super-forms/uploads/php/files/fa20f0561bf0ca6829144b21f752653c/85934583428.pdfIn PDF document text
    • http://franzoesischebulldoggen.eu/userfiles/file/susas.pdfIn PDF document text
    • https://www.hdontheroadnapoli.it/wp-content/plugins/formcraft/file-upload/server/content/files/160d93d5325959---wosube.pdfIn PDF document text
    • http://er-trans.com/img/produkty/files/80360224302.pdfIn PDF document text
    • http://oryginalnedekoracje.pl/userfiles/file/84483818807.pdfIn PDF document text
    • http://zoltysnieg.pl/pliki_wyswig/files/81804877444.pdfIn PDF document text
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c8c4a11de94---bezidifuxigesipema.pdfIn PDF document text
    • https://efsanepin.com/calisma2/files/uploads/8857527171.pdfIn PDF document text
    • https://capital-publishing.com/ckfinder/userfiles/files/97758027085.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609c11d955148---wovajagozagezuxexevalebid.pdfIn PDF document text
    • https://autoroman-service.ro/imagini_ws/32805627609.pdfIn PDF document text
    • http://sieckultury.pl/wp-content/plugins/super-forms/uploads/php/files/129a5cc0b154a4c53be75e50a6efa465/48461595435.pdfIn PDF document text
    • https://corpeverest.com/ckfinder/userfiles/files/69172679662.pdfIn PDF document text
    • https://chocoinmobiliario.com/wp-content/plugins/super-forms/uploads/php/files/d6b0049fe2ff644e44f8465d777d0bca/20497374626.pdfIn PDF document text
    • https://www.intermediastudios.com.mx/wp-content/plugins/super-forms/uploads/php/files/b3c7eb426834785e8982f3d16d001dbb/jizokilaniwogulukix.pdfIn PDF document text
    • https://www.sacproblemleri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e2b088033b---xotameraxer.pdfIn PDF document text
    • http://tfforming.ru/d/files/23475050472.pdfIn PDF document text
    • https://widepolymers.com/userfiles/file/vetefujujagosufarowudav.pdfIn PDF document text
    • https://www.nrlandscapes.co.uk/wp-content/plugins/super-forms/uploads/php/files/4253d3561bd5c157961740ff488592ec/1797584404.pdfIn PDF document text
    • http://geo-equipe.it/userfiles/files/jakufazebevo.pdfIn PDF document text
    • http://franzoesischebulldoggen.eu/userfiles/file/tuxatola.pdfIn PDF document text
    • 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_off0001159e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1159E 10464 bytes
SHA-256: 3008a94614557ac890cd1e7b119a4b1dad331508bdf0b3d753e436cc0a2e252e
font_01_sfnt_off00012d7d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12D7D 19172 bytes
SHA-256: c51ee3002d294f184ee4d276fb88f3fed58127c6bf2d1d7fcd80c5e9bea0debf
font_02_sfnt_off00015f97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x15F97 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1