Malicious PDF — malware analysis report

Static analysis result for SHA-256 5b41249814350fb2…

MALICIOUS

PDF

80.9 KB Created: 2021-08-04 23:00:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c49ec6df09bba4e1603a6aee81b36357 SHA-1: 9025e2d557611b532a8412940e93da575f11a80f SHA-256: 5b41249814350fb217be68b637f45d05d0b697faf7cb414a1c821108ac0d3ff0
172 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains an embedded JavaScript stream and multiple external URIs pointing to link farms hosted on compromised WordPress sites. These link farms likely serve as a lure to trick users into downloading a malicious payload, as indicated by the ClamAV detection and ML classifier flagging this PDF as malicious. The presence of embedded JavaScript suggests potential for further malicious actions beyond simple redirection.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

Heuristics 8

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a7e320b4640---92633441826.pdf
    • https://www.prowallpanama.com/wp-content/plugins/super-forms/uploads/php/files/28e76ffbeb92286f56bf7673bc3efa13/zirizorowigaki.pdf
    • http://prplus4u.com/ckupload/files/nibuxitesugebuzumepa.pdf
    • http://autosoftware.company/autoresponders_images/files/kuzekaxoke.pdf
    • https://regenerativetherapyforpain.com/wp-content/plugins/super-forms/uploads/php/files/5aca4e2ad0789adc20386570e97ac8ce/25475489300.pdf
    • http://debeight.net/UserFiles/File/napep.pdf
    • http://mesotects.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608abf4f7c760---sigemidevelojetiluw.pdf
    • http://somersetcountybar.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/xawovip.pdf
    • http://waelfawzy.com/userfiles/file/16172179157.pdf
    • https://homeaestheticsllc.com/wp-content/plugins/super-forms/uploads/php/files/de1b0175305bb3e0eff6259dab050395/26410761628.pdf
    • http://becro-plast.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160c52834b5b20---wopujodifebuji.pdf
    • https://lentes123.com/aym_image/files/87273665095.pdf
    • http://all-vehicle.net/js/upload/files/50787314973.pdf
    • https://oiweld.com/wp-content/plugins/super-forms/uploads/php/files/9ff8020cd7758aaf338ae25a8bfb66fd/30420468066.pdf
    • https://moma-restaurant.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c607d55578a---54891190767.pdf
    • https://www.physioaktivkramer.de/wp-content/plugins/formcraft/file-upload/server/content/files/16096919bef5e2---77838868932.pdf
    • http://karate-talence.com/newsite/userfiles/files/47123328027.pdf
    • https://europartner2.pl/uploads/bezububozebilu.pdf
    • http://www.netcorp.hu/data/editorfile/29538655008.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1607ff7ba5f5eb---88058723763.pdf
    • http://accessiblevehicleservices.com/userfiles/file/nebifaziwituwev.pdf
    • http://pnktools-th.org/ckfinder/userfiles/files/96189022746.pdf
    • http://www.next-conseil.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16082cb626b520---gelade.pdf
    • http://graphicon.hu/wp-content/plugins/formcraft/file-upload/server/content/files/1607ecea295a02---21727037439.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=free+youtube+mp3+downloader+for+mac
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d804.bin
bfd771ec5515ffa08c4de932663dae55d5f911579eab6f534222ca189316c94b
pdf-font-stream PDF embedded font (sfnt) at offset 0xD804 11112 bytes
font_01_sfnt_off0000f1d4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1D4 16792 bytes
font_02_sfnt_off000109e6.bin
bb5e891547b4910bdbcc6952737d68611601d7d44c322b0ecdc5be2d39df8d4d
pdf-font-stream PDF embedded font (sfnt) at offset 0x109E6 16520 bytes