Malicious PDF — malware analysis report

Static analysis result for SHA-256 40b48d648d6a1322…

MALICIOUS

PDF

75.3 KB Created: 2021-09-10 10:52:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dfd3eba2bae47536f8da1354bddf7794 SHA-1: c96b56f52957e6c92a6297ac7e48db75e71a51f7 SHA-256: 40b48d648d6a13225b6abe2d2613548330d0e55e22523f0d733c529d664d00fa
164 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or distributing further malware. The presence of a link farm on potentially disposable hosting further supports a malicious purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9976

Heuristics 7

  • 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.
  • Urgency / deadline lure low SE_URGENCY_LURE
    Document contains urgency or deadline language ('account will be terminated', 'action required within 24 hours', etc.) — useful context, but low-signal without other findings
  • 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://www.tratedu.net/ssss2018/assets/143ad273/ckfinder/core/connector/php/upload/userfiles/files/3e3d6e21081b98a9a912c54a93c60b9d.pdf
    • https://lmetinternationalschool.in/ckeditor/ckfinder/userfiles/files/76291736829.pdf
    • https://on-call-anatomist.org/ckfinder/userfiles/files/68854750397.pdf
    • http://dobryremont.pl/ebobas/portal/app/webroot/img/tmp/file/16310070979551.pdf
    • http://www.akutrans.com/wp-content/plugins/formcraft/file-upload/server/content/files/16137b45a0fd28---89441304235.pdf
    • http://fge-service.com/userfiles/file/52020192218.pdf
    • http://www.radiopopiatej.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354e5418473---bunawigeja.pdf
    • https://xn--80aesyq.xn--p1ai/files/file/bawegakonolarunoferalaru.pdf
    • https://fermuar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613386fdcd4f6---fejenukonidiselizawisu.pdf
    • http://www.olympussverige.se/wp-content/plugins/super-forms/uploads/php/files/p82jnnlcif1q4bbudbrph2ki3i/gobelonugod.pdf
    • http://hoya889.com/upfile/files/20210903225118.pdf
    • https://digbijoynath.in/uploads/userfiles/files/zimikexeweje.pdf
    • http://elitvorota.ru/f/file/zegelujizekesitubop.pdf
    • https://isabellepieman.com/userfiles/file/penanuxafekogigoxamevuvef.pdf
    • https://drakbera.com/ckeditor/ckfinder/userfiles/files/91755156955.pdf
    • http://protectakoteasia.com/ckfinder/userfiles/files/47438873536.pdf
    • https://bedandbreakfastchia.it/userfiles/file/xotufesemaz.pdf
    • http://asesorgubernamental.com/images/file/26560455007.pdf
    • https://www.cdscabling.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1613b09edde2b6---5464821807.pdf
    • http://seoulmenu.com/uploads/files/mamabaw.pdf
    • https://shian-jin.com/UserFiles/files/gajedatobulogi.pdf
    • http://scvumaichiramen.com/uploads/files/26397320390.pdf
    • https://emergent-partners.com/wp-content/plugins/formcraft/file-upload/server/content/files/161341ae462d65---79510049664.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/cv9VXjIrmdE/uplcv?utm_term=browsec+pro+apk
    • 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_off0000c417.bin
6345c7f9f6d1627a3d26101efd798ceaf88fedcff72029d28070c28cdd349158
pdf-font-stream PDF embedded font (sfnt) at offset 0xC417 17204 bytes
font_01_sfnt_off0000f06b.bin
ca00c9fc3955131e0db9aeecab18e01099b01c40af3ec5d3167e32b4092267e2
pdf-font-stream PDF embedded font (sfnt) at offset 0xF06B 10260 bytes
font_02_sfnt_off000107c4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x107C4 16792 bytes