Malicious PDF — malware analysis report

Static analysis result for SHA-256 f23f827dc4138e96…

MALICIOUS

PDF

94.9 KB Created: 2021-07-01 23:45:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 57e92cf1f1b233de74a3244575122b79 SHA-1: 6adab1b54d9f6dd08e852e68fe91daa9279c924c SHA-256: f23f827dc4138e962b5d40a088276bd15103a193201c22fe828ff062f3dd97f9
156 Risk Score

Malware Insights

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

The PDF contains a link farm pointing to numerous compromised WordPress upload directories and disposable hosting, indicating a phishing or malware distribution attempt. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to exploiting users via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9820

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 http://teplospectr.ru/images/files/39626129204.pdf In PDF document text
    • https://creativesilhouettes.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1608838542efb7---12455390201.pdfIn PDF document text
    • https://roadtoring.com/wp-content/plugins/super-forms/uploads/php/files/390b91598f25756e6fd77d2325c0d910/59561690279.pdfIn PDF document text
    • https://paidionresearch.com/userfiles/files/bevarex.pdfIn PDF document text
    • https://thriveelearning.com/wp-content/plugins/super-forms/uploads/php/files/5fc8b4feee4a839cb1ab28269c930bdc/22568269962.pdfIn PDF document text
    • https://t4g.nasscomfoundation.org/wp-content/plugins/super-forms/uploads/php/files/le9u1lak7kq07qhv3l0nelor04/bajipik.pdfIn PDF document text
    • https://pensionatiitalianiinportogallo.it/wp-content/plugins/super-forms/uploads/php/files/b8814876d29232f68b03503aa49ed3ec/kuvigomixuwo.pdfIn PDF document text
    • https://centar-znr-zop.hr/wp-content/plugins/formcraft/file-upload/server/content/files/160761b98e0f66---56309448508.pdfIn PDF document text
    • http://penoplex24.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16076dc5911a46---zusozikiwaximoli.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607f39d17195b---fusijonivo.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/ku488247u2a30bte1ao8oovac5/bajixozenumiroz.pdfIn PDF document text
    • https://www.dazzlingdecor.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1609f8998d6578---vigifisawewajuleguse.pdfIn PDF document text
    • https://kham.vn/userfiles/file/93505348602.pdfIn PDF document text
    • https://bikinibody.be/wp-content/plugins/super-forms/uploads/php/files/7ui091eaqju6lskg8projoots0/tosokojiwudafife.pdfIn PDF document text
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/160713b1775344---zifagovirowum.pdfIn PDF document text
    • http://www.lnk-creation.fr/upload/file/buveluxejuxu.pdfIn PDF document text
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/a0f8eff47563a19e2d7b393847509303/5409317690.pdfIn PDF document text
    • http://hopkins1983.com/clients/861771/File/31854042234.pdfIn PDF document text
    • http://libron.pl/fckupload/assets/file/gusiwilejonevelilis.pdfIn PDF document text
    • http://xn----8sbnbd9chja.xn--p1ai/userfiles/file/sipimodu.pdfIn PDF document text
    • https://aquariumfargo.com/wp-content/plugins/super-forms/uploads/php/files/bcb1df7f0ffd8f13e019c97513a70464/19774890291.pdfIn PDF document text
    • https://www.endthestigmacounselling.com/wp-content/plugins/super-forms/uploads/php/files/5eq44pdhcl8febfci3157ituuv/2567611347.pdfIn PDF document text
    • https://atraba-holding.com/userfiles/file/tebotepijavexarusebov.pdfIn PDF document text
    • http://ideas4mypool.com/userfiles/file/rigiwi.pdfIn PDF document text
    • https://www.lang-mayer.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c532cfb16e7---saxuvetomiregu.pdfIn PDF document text
    • https://lesfeesdelhetre.fr/upload/files/15519084210.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/S30rS-6n6vg/uplcv?utm_term=the+high+middle+agesPDF 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_off00011033.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11033 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0001284a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1284A 10236 bytes
SHA-256: efe023a76ea3a1c8f80229cf53c1b2ba5d3e1fab2acb9b2c0a8e996d49ab6e69
font_02_sfnt_off00013f02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13F02 17672 bytes
SHA-256: ac583cc1b3033651d0dc01ecccd9959c5501f248b9f3395301b47406ee66a7fa