Malicious PDF — malware analysis report

Static analysis result for SHA-256 50b1779024c93bad…

MALICIOUS

PDF

90.2 KB Created: 2021-07-18 08:49:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: ca04f3193b01c1f07fa2e8bf212f4f05 SHA-1: 38841c10bcf4ed1ed1dbf768769b517b6a71f572 SHA-256: 50b1779024c93bad851208b4fe03ae0f3a1b008630bf847ef330c010a1fd1b28
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.001 User Execution: Malicious Link

The PDF contains a link farm pointing to multiple compromised CMS upload locations, indicating an attempt to host malicious files or redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware distribution. The document body is heavily obfuscated and unreadable, providing no direct clues to its purpose.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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://ambalatender.com/upload/files/61491023773.pdf In PDF document text
    • https://functionalmovement.gr/wp-content/plugins/super-forms/uploads/php/files/28b0396bacde7266ab9ab24dff9046fa/71475661420.pdfIn PDF document text
    • http://thanuyentea.com/ckfinder/userfiles/files/pogetulatuteroled.pdfIn PDF document text
    • http://www.sevenchurchestour.net/seven/wp-content/plugins/formcraft/file-upload/server/content/files/160853e799e69e---zinuxideguvi.pdfIn PDF document text
    • https://iamluno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aaba3c274fd---gelibunemowotapiberu.pdfIn PDF document text
    • http://mingzhicc.com/userfiles/files/23205885612.pdfIn PDF document text
    • http://etoprosto.ru/ckfinder/userfiles/files/vijebaxuguwa.pdfIn PDF document text
    • http://www.jhannahs.com/wp-content/plugins/formcraft/file-upload/server/content/files/160da1c4be57b8---34299816000.pdfIn PDF document text
    • http://www.kocay.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160c4df8ef3f55---jubajafujerenefu.pdfIn PDF document text
    • http://andreagarciam.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609ea53b63c11---riwudisigojos.pdfIn PDF document text
    • http://actionelectric.pt/www/wp-content/plugins/formcraft/file-upload/server/content/files/1608e7d8458dfe---60669605094.pdfIn PDF document text
    • http://vtdsbinhthuan.vn/public/uploads/userfiles/file/5656269897.pdfIn PDF document text
    • http://atlantichomeportugal.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080efb006755---60587203988.pdfIn PDF document text
    • https://ctapigroup3.com/contents//files/6036027104.pdfIn PDF document text
    • http://botosani.ro/img/uploads/file/godajepavekujerefesir.pdfIn PDF document text
    • https://socialchangefactory.org/wp-content/plugins/super-forms/uploads/php/files/dcf3db6ce96d82152171eaeee21cdcfc/65012793636.pdfIn PDF document text
    • http://www.photonics-science.com/ckfinder/userfiles/files/19696076106.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/kpc1pl4bhe55ces2rqsacligf7/93432270648.pdfIn PDF document text
    • https://sdyh.gr/wp-content/plugins/super-forms/uploads/php/files/745rsd92as9niggqs74qnngif5/nujenizurubates.pdfIn PDF document text
    • http://mijneigenlift.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160e528e51ece3---saxadumaxuzaw.pdfIn PDF document text
    • https://alnahamgroup.com/userfiles/file/4167025096.pdfIn PDF document text
    • http://goref.ru/files/file/9470346732.pdfIn PDF document text
    • https://primax.fr/wp-content/plugins/super-forms/uploads/php/files/tfnit9nso69nqn4opg2c8b3t22/27617864984.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/BvfzZFkJO3s/uplcv?utm_term=richest+house+in+gta+5PDF link annotation
    • 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_off0000fd97.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xFD97 17508 bytes
SHA-256: 1d38a2d733c85c70d5681565f8103a6115dae53c9ccc1b88618007913a263952
font_01_sfnt_off00012b6e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12B6E 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00014385.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14385 10640 bytes
SHA-256: ffcaad16bfd5c82b27c1408ceb643ce44b3a50f52628cd126f8ce38f3abd7613