Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f882c8804e7eb0f…

MALICIOUS

PDF

98.8 KB Created: 2021-09-11 19:27:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b47be96e987e62fd9d831c343f998be0 SHA-1: 70029e6e2ea9fdc3e4e832aa5da96cbd59da838e SHA-256: 7f882c8804e7eb0f34e325515175285c2722aedb791c8a949aac80b7cd72d2f6
196 Risk Score

Malware Insights

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

The sample is a PDF document flagged by ClamAV as a phishing trojan. Heuristics indicate it contains a link farm pointing to compromised CMS uploads and disposable hosting, likely serving as a lure for remote support tools. The embedded URLs and link farm structure suggest an attempt to trick users into downloading and executing a malicious payload, potentially via a second-stage download.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9600

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Remote-support tool lure high SE_REMOTE_SUPPORT_LURE
    Document instructs the user to install, open, or connect with a remote-support tool such as AnyDesk, TeamViewer, Quick Assist, or ScreenConnect — high-risk in an unsolicited document
  • 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://vantainoidia.vn/ci/userfiles/files/99500140907.pdf In PDF document text
    • http://xn--9i1b14l32gg2dsybq3b.com/upload/fckeditor/file/9205858251.pdfIn PDF document text
    • https://mexico-airport-transfers.com/ckfinder/userfiles/files/lijebuvo.pdfIn PDF document text
    • https://rjpexport.com/files/57798357627.pdfIn PDF document text
    • http://tnslib.net/userfiles/files/74467619239.pdfIn PDF document text
    • http://xn--d1achljw0b.xn--p1ai/content/upload/84391054340.pdfIn PDF document text
    • http://nbnjl.com/userfiles/files/fojevugiw.pdfIn PDF document text
    • http://tumwebthailand.com/ckfinder/userfiles/files/59939224845.pdfIn PDF document text
    • https://fobh.net/userfiles/files/44960709174.pdfIn PDF document text
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/15ab42071f3d611e1f3ca4cc634c1b30/48640426444.pdfIn PDF document text
    • https://vrrc.heart.net.tw/ckfinder/ckfiles/files/95889448743.pdfIn PDF document text
    • http://hilimall.ae/uploads/files/webifegekeleritiposa.pdfIn PDF document text
    • https://stomatoloska-ordinacija-rijeka.com/files/91959818441.pdfIn PDF document text
    • http://leaders-adv.net/userfiles/file/9199152646.pdfIn PDF document text
    • http://crystalnymph.by/wp-content/plugins/super-forms/uploads/php/files/d425de1167d7ee5e6a0002896fd6b141/30163368780.pdfIn PDF document text
    • http://arcstema.com/userfiles/files/kalotabusinomarabazewawe.pdfIn PDF document text
    • https://777mto.com/contents/files/zulavaku.pdfIn PDF document text
    • https://luiginoiobbi.com/userfiles/file/55279594541.pdfIn PDF document text
    • http://cesishotel.lv/res/wysiwyg/file/94805266252.pdfIn PDF document text
    • http://qualityspices.in/ckuploads/files/1346033517.pdfIn PDF document text
    • http://wsystem.sk/userfiles/files/kilutilot.pdfIn PDF document text
    • http://thepokewave.com/uploads/files/60996644797.pdfIn PDF document text
    • http://protech.com.ng/wp-content/plugins/formcraft/file-upload/server/content/files/1613be6f813dc8---78773027554.pdfIn PDF document text
    • http://hcstonetw.com/uploads/files/202109081703225448.pdfIn PDF document text
    • http://www.xpresswedding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16139e5efccfde---dekematusir.pdfIn PDF document text
    • http://hoshitorionline.com/uploads/files/bejajegimugijirubadabepus.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=windows+10+iso+crackPDF 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f2d0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF2D0 10432 bytes
SHA-256: d437fce72caf99b0b25ab7eb8c9db4fd9d2e623c002072050e6b916dd46fed68
font_01_sfnt_off00010aa8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10AA8 22848 bytes
SHA-256: aa3007d8c664fc6ccd6578b4daaa150d660985bfe81b5e6b0ce75e40c99f36e0
font_02_sfnt_off0001461e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1461E 1820 bytes
SHA-256: ef4c56b83544acc0eae329b123dcb13384a4443b8ee25b6b011fcec9f25c534c
font_03_sfnt_off00014ea8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14EA8 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_04_sfnt_off000166b9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x166B9 16192 bytes
SHA-256: 126aabc53b187bc4421529373f04e2f66a11804dfeaeb35cb650b132d56c1dbd