Malicious PDF — malware analysis report

Static analysis result for SHA-256 c93c1ae1c19b2dda…

MALICIOUS

PDF

84.2 KB Created: 2021-09-08 02:12:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 14492c4adf0efc2ae86834073f6af2c9 SHA-1: 99497a74ce47942e64117cd4e551fffc352b98d9 SHA-256: c93c1ae1c19b2ddac4fc8befcf6372d0523768c355ded1330feffb124ebcb70b
156 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 related to phishing or malware delivery through these linked sites. The PDF itself does not contain readable content but functions as a redirection mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • 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.
  • 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://sad-azov.ru/wp-content/plugins/super-forms/uploads/php/files/f89378759da59f813b83fff5b5a8962f/88660549092.pdf
    • http://az4group.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a84bdcd5bac---jevoluvabekewumekazikirir.pdf
    • http://otelm4b.ru/admin/ckfinder/userfiles/files/38319661569.pdf
    • http://czdashan.cn/uploadfile/file/2021051602095973499.pdf
    • https://mrmobilewebsite.agency/wp-content/plugins/super-forms/uploads/php/files/1076a9429291804509cb688453d7586a/10613052902.pdf
    • https://alfa-clining.ru/wp-content/plugins/super-forms/uploads/php/files/e76168f1e72b1975738bfe4eeedf7bde/nizipuvad.pdf
    • https://hoovermaids.com/wp-content/plugins/super-forms/uploads/php/files/adbf8bfff6efb1777cc40333112bd1c9/91494470208.pdf
    • https://toppelletmachine.com/d/files/8585261338.pdf
    • http://koszyczarek.pl/userfiles/file/64509049674.pdf
    • https://zhongzing.com/uploads/files/202108211230362768.pdf
    • http://cdkkck.com/uploadfile/file/20210729222243.pdf
    • https://abbma.in/admin/uploads/file/sutugoz.pdf
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8dbd17d95---lepajilinubet.pdf
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606cb0ebd7446---64069823279.pdf
    • https://asiaviews.org/wp-content/plugins/super-forms/uploads/php/files/a2r2usuh88rl4kvv0m9ik6mnp4/38928110408.pdf
    • https://winston-woodward.com/wp-content/plugins/super-forms/uploads/php/files/c5f8569be4abea9695507d605f497da7/70653313083.pdf
    • http://broadmoor79.com/clients/864886/File/18102577807.pdf
    • http://queuemanagementsystems.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a5ad1356a4f---semekikin.pdf
    • https://alphaveneers.co.uk/wp-content/plugins/super-forms/uploads/php/files/70f626521c62d4a2854429afb2589a3d/53211766393.pdf
    • http://nacnsuaa.com/clients/4/49/49ab1acc6c62b5a39110d621a19f71c0/File/babesasumarararinasizak.pdf
    • http://metzpaintings.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a67578ca02f---wezekixosanageromexe.pdf
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/160fc2c980aa0b---1243638252.pdf
    • https://associazionedynamica.it/uploads/file/11151481085.pdf
    • https://immo-cjeanpaul.lu/userfiles/files/susomejofenuxuka.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/fzgW7-mxBc0/uplcv?utm_term=plural+worksheets+y+to+ies
    • 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_off0000e094.bin
54268456daf5b83d87cc076eac17cab5f7d4a34b5518cda02d86dc00469d7205
pdf-font-stream PDF embedded font (sfnt) at offset 0xE094 10496 bytes
font_01_sfnt_off0000f8b7.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF8B7 16792 bytes
font_02_sfnt_off000110c9.bin
6f4aa9bd7191e5cda3eae59cfc1e4701e6ace3ef1c98e6f820c07f3eb23d16f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x110C9 19484 bytes