Malicious PDF — malware analysis report

Static analysis result for SHA-256 b064a89299773b8a…

MALICIOUS

PDF

70.2 KB Created: 2021-08-30 08:52:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 26a41d5dafca0ace159c3929346cd1ae SHA-1: 5f326b3d383b4800d186cfa91feb43658cdb1840 SHA-256: b064a89299773b8ab9fcc3ffb5a6727ad2f545a14bf75d533ddce67d6e14c081
156 Risk Score

Malware Insights

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

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress sites, likely serving as a distribution point for further malicious content or phishing attempts. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user consumption but rather as a vehicle for the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://www.kngroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160989853f128c---ralerowewesasenowe.pdf
    • https://www.etbsupplies.com/wp-content/plugins/formcraft/file-upload/server/content/files/160dc920e2561c---zuligusififipokasuwuvop.pdf
    • http://pck.malopolska.pl/wp-content/plugins/super-forms/uploads/php/files/cfa27ebcc3ad6b1dc91cb5245eb32cbb/2949686845.pdf
    • https://centrobrands.com/wp-content/plugins/super-forms/uploads/php/files/52640f255030442279a213786c15b3d7/bovemerinijesuj.pdf
    • http://grapevinewinerytrail.com/clients/876125/File/83262054992.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aba72a946aa---girowa.pdf
    • http://blueleaves.ru/userfiles/file/9764053820.pdf
    • https://www.piramideidiomas.com/ckfinder/userfiles/files/roxedilesipukotuwivuwuf.pdf
    • https://thedestinbeachhouses.com/wp-content/plugins/super-forms/uploads/php/files/72366ad254b219a1cfa133f1f657e1fd/95643643033.pdf
    • https://cylinder96.ru/admin/ckfinder/userfiles/files/4459785615.pdf
    • https://claphamjunction.com.au/wp-content/plugins/super-forms/uploads/php/files/14c31ff4aa155614818ef2a9f7f5fdd7/zutasopiv.pdf
    • http://macautemple.com/userfiles/file/fejubejinagukabimavin.pdf
    • http://www.makattakasinti.com/wp-content/plugins/formcraft/file-upload/server/content/files/160850df0f322a---61943760209.pdf
    • http://relocationservicesgroup.com/wp-content/plugins/formcraft/file-upload/server/content/files/160770ac4104e8---45251662054.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612c24fda7ec7---wixozumodufenenigapaz.pdf
    • http://grandinspirations.com/clients/75274/File/97345616952.pdf
    • http://www.kinoimaging.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1608ceb3309529---milamaduso.pdf
    • https://lightspec.ca/wp-content/plugins/super-forms/uploads/php/files/17182dcff4851fdd3457c707c82174e5/60581671484.pdf
    • https://adikketiga.com/contents//files/1911583058.pdf
    • http://www.dilipprabhavalkar.com/images/file/46644813157.pdf
    • http://eatatrudy.com/uploads/files/sezupoweke.pdf
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/fc9d07bff8e991a61e5058ff85810c07/94138761843.pdf
    • http://herodumpsterrental.com/wp-content/plugins/super-forms/uploads/php/files/b822988049cb4fe243c4c9d009aa577a/41711334292.pdf
    • http://salinahighschool1968.com/clients/3/33/33fcb9b832a528c934b1ac42c6b88a99/File/15792923416.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=specific+heat+of+air+and+water
    • 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_off0000b7c6.bin
a139a7fde262b3a206fa167699f4784be86e8a1c0c02b77a814a3d8a03e412aa
pdf-font-stream PDF embedded font (sfnt) at offset 0xB7C6 10664 bytes
font_01_sfnt_off0000d034.bin
5203f58a5730f8fa3765007dcd4aac8e8661568127ecb9b9952befe9bcfbb34f
pdf-font-stream PDF embedded font (sfnt) at offset 0xD034 14096 bytes
font_02_sfnt_off0000f33b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF33B 16792 bytes