Malicious PDF — malware analysis report

Static analysis result for SHA-256 400b72c677bfc951…

MALICIOUS

PDF

75.0 KB Created: 2021-09-02 12:09:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: 9fd45d8db10ce01dd609dc455c08accd SHA-1: dad033ab698d149bc50be684e3124960feae0cfc SHA-256: 400b72c677bfc951bb91a6a962257607eb25b3b67a9fde714510570518678c6a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of PDF_URI and PDF_SEO_DISPOSABLE_LINK_FARM heuristics further supports this. No scripts were extracted, but the structure and URL patterns are consistent with phishing or malware distribution lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://crewmak.ru/uplcv?utm_term=penyuluhan+bahaya+merokok+pdf PDF link annotation
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/16081ca7d434f2---lapuxerilubeki.pdfIn PDF document text
    • https://www.ergunaygoren.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072869291ed0---86217175248.pdfIn PDF document text
    • https://poulinstrapscan.com/userfiles/file/tedibivegowev.pdfIn PDF document text
    • https://unicornproduction.gr/wp-content/plugins/super-forms/uploads/php/files/fefdcd5e611d2840a628c712c67520be/8097725948.pdfIn PDF document text
    • http://xn--80aafbladvtgxneccoge3bt.xn--p1ai/pict/file/23408635052.pdfIn PDF document text
    • http://takeacode.net/user/d41d8cd98f00b204e9800998ecf8427e/file/sakobusefo.pdfIn PDF document text
    • http://halvani.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b1f0d353366---jiwaf.pdfIn PDF document text
    • http://career-id.org/ckfinder/userfiles/files/fefirenosajevoko.pdfIn PDF document text
    • https://christembassybarking.org/wp-content/plugins/super-forms/uploads/php/files/ad170d34a45795ddc9b70b9d8b23ff19/86919287400.pdfIn PDF document text
    • http://live-lessons.net/lcj/web/uploads/assets/file/loriwifobapojuvono.pdfIn PDF document text
    • https://magiccat.pro/ckfinder/userfiles/files/92595527882.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/73c2c52c04eddb064ba36b63d3d0b5be/91291512568.pdfIn PDF document text
    • https://estidevelopers.com/wp-content/plugins/super-forms/uploads/php/files/79def61d20907f67c875c98a15b6252f/mixixififudoxez.pdfIn PDF document text
    • http://comicpapyrus.com/wp-content/plugins/super-forms/uploads/php/files/771c7b987cd0f1d92ae731541a750de9/69443075256.pdfIn PDF document text
    • http://sarljarry.fr/userfiles/file/45206786918.pdfIn PDF document text
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bedda20787e---73687235603.pdfIn PDF document text
    • http://pumarecovery.com/userfiles/files/94481322362.pdfIn PDF document text
    • http://aesg2edcv.handylover.com/upload/files/28260056299.pdfIn PDF document text
    • https://congthuonghotel.vn/app/webroot/files/images/pages/files/79366150022.pdfIn PDF document text
    • http://nkmate.com/FileData/ckfinder/files/20210720_B72B646E75B75703.pdfIn PDF document text
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/d892f37be7e74123b5de27b6232f7d75/31490188956.pdfIn PDF document text
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609478f5b1518---92665509855.pdfIn PDF document text
    • https://dipinkrishna.com/wp-content/plugins/formcraft/file-upload/server/content/files/160beb06371041---91397757929.pdfIn PDF document text
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/s995d54usu1v9nmlkdainn477q/42564910304.pdfIn PDF document text
    • https://aimara-bg.com/userfiles/file/sagemuzej.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_off0000c3b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC3B0 16396 bytes
SHA-256: 6eb55f4a86e49efd7b5835661373e0193dc769768c22d11cb504e63bbdcfe197
font_01_sfnt_off0000ed8c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED8C 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off000105a3.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x105A3 10852 bytes
SHA-256: 56d2fa49e588ec9d521bd61b18c499dd78cbc7abe6b470810f93c51b9f739b0b