Malicious PDF — malware analysis report

Static analysis result for SHA-256 4446959e137232c3…

MALICIOUS

PDF

109.9 KB Created: 2021-09-20 01:27:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: fa98ff57596a74169b0a17a6d135f82a SHA-1: e5798f771a2fe6bc6d4acb98eb38538d97b27274 SHA-256: 4446959e137232c3218944239afc0a0518370f812167f4a2a4e751a7e22e45b0
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains a link farm with numerous URLs pointing to other PDF files, many hosted on compromised CMS uploads. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather as a vehicle for hosting malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9968

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://feuerwehrobrigheim.de/upload/files/25731320480.pdf
    • http://0575zl.com/userfiles/file/rodopumosawiref.pdf
    • http://iamsong.vn/uploads/files/zopadepepud.pdf
    • http://businessdevelopmentcenter.pl/uploads/userfiles/files/5769119835.pdf
    • http://cdseoulps.com/uploadfile/fckeditor/file/12739681875.pdf
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613b4606ef84f---75947982252.pdf
    • http://apsencollege.org/test/fckeditor/file/pofexiwefanutunokuvureka.pdf
    • http://www.vandiestbrandstoffen.be/uploads/files/96787647561.pdf
    • http://inewbus.com/wp-content/plugins/super-forms/uploads/php/files/i30v79f7r07vpbqflmkifg1m90/28000688236.pdf
    • http://capitaldanceacademy.com/userfiles/files/26192498559.pdf
    • http://abwlanham.com/uploads/files/miviwuzulupazaruzama.pdf
    • http://dietgame.net/admin/fckeditor/data/file/20210906141934.pdf
    • http://mavelikaradiocese.org/rapha/ckfinder/userfiles/files/30891059497.pdf
    • https://www.frontieregypt.com/sites/all/libraries/ckfinder/userfiles/files/zodasonewodufef.pdf
    • http://tuvantindat.com/uploads/2021-09-08/images/files/49128112356.pdf
    • http://verkoop-je-wagen.be/wp-content/plugins/formcraft/file-upload/server/content/files/16134c120588f0---60767955572.pdf
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/1614478ea10649---golubibivomepajisoxikot.pdf
    • https://martabaktelor.com/contents/files/55235516099.pdf
    • https://www.cifphosteleriayturismo.es/ckfinder/userfiles/files/pugoxuzimifabawigat.pdf
    • http://niengrangchuyensau.com/upload/contentFile/file/2090833797.pdf
    • https://hearing-outlet.com/uploads/files/202109150254402074.pdf
    • http://www.videobezopasnost.ru/ckfinder/userfiles/files/63589199899.pdf
    • http://ydyb.com/filespath/files/20210903093343.pdf
    • http://superazs.ru/images/news/file/kuvinebogofimitikixa.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/Om9ozkHLxGw/uplcv?utm_term=explain+rom+in+computer
    • 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_off000145b0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x145B0 16792 bytes
font_01_sfnt_off00015dc2.bin
f713253a4e028e0ff6185c5f1f55b01c2862b8bcced43d854c06329bf04075e4
pdf-font-stream PDF embedded font (sfnt) at offset 0x15DC2 19996 bytes
font_02_sfnt_off000191de.bin
0a43375630ad03b878b78cdb60d4aa0de2f9a38e591c4347b436016f4f951baa
pdf-font-stream PDF embedded font (sfnt) at offset 0x191DE 10552 bytes