Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef2c7bfee977c4f1…

MALICIOUS

PDF

111.3 KB Created: 2021-09-18 01:01:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: 8a527eea5b45ceaccfa0cb75f86352a2 SHA-1: 91a0b51b916615fe8ac49b4889ffb3ff07920194 SHA-256: ef2c7bfee977c4f1b9aee07cb7baaa9a9f0647d128169e0deef7b4225dbfafec
156 Risk Score

Malware Insights

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

The PDF document contains numerous embedded URLs, many of which point to compromised CMS uploads and disposable hosting domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution via these links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9986

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://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/49f063078fc585fd4e4dc6ce3966778c/34935065234.pdf In PDF document text
    • http://xn--tnqz8hz5cb8l.com/upload/files/jazajixotok.pdfIn PDF document text
    • https://taumed.kz/upload/2021/09files/210903091554618307551z3.pdfIn PDF document text
    • https://truckforceone.com/upload/editor/file/tobofimom.pdfIn PDF document text
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16136e34abaf41---79848980986.pdfIn PDF document text
    • http://www.mousumibanerjee.com/fckimages/file/24382837352.pdfIn PDF document text
    • http://fairfresh.net/assets/admin/ckeditorimage/files/59442748324.pdfIn PDF document text
    • https://baxsporthorses.com/userfiles/file/xiwezavipitirap.pdfIn PDF document text
    • http://raduzhniy.com/wp-content/plugins/formcraft/file-upload/server/content/files/161354f436cc6a---pirul.pdfIn PDF document text
    • http://cameranichietsu.com/luutru/files/ladewikasufoxuzefebigi.pdfIn PDF document text
    • http://firewheels.pe/userfiles/file/pekujumifetezaxinu.pdfIn PDF document text
    • https://rolcsi-bau.hu/userfiles/files/kukajezuzisegijiluxuduv.pdfIn PDF document text
    • https://izr.fr/files/54856913148.pdfIn PDF document text
    • http://gzperson.com/uploadfile/files/69421125805.pdfIn PDF document text
    • http://zekejozsef.eu/FCKfeltoltott/file/2200717024.pdfIn PDF document text
    • http://escolacaritas.com/wp-content/plugins/formcraft/file-upload/server/content/files/161450feed2232---73368539111.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161450ea01524f---88084082760.pdfIn PDF document text
    • https://webmenuplus.com/images/file/12224187598.pdfIn PDF document text
    • http://tnetimes.kr/upload/file///52998497555.pdfIn PDF document text
    • http://ppogrimall.com/upload/editor_image/file/werifevowex.pdfIn PDF document text
    • http://thessalonikiflights.com/files/files/8739020277.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/BkSY9tpko7c/uplcv?utm_term=how+to+update+my+phone+androidPDF 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_off00014d27.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14D27 19000 bytes
SHA-256: 203af9a94e806e821b4463f569610587ccc5bd39b2d606663b48d2567eac2cbb
font_01_sfnt_off00017f06.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x17F06 10732 bytes
SHA-256: eba49b15ccbad33beb74e886876322d34fc8a3e435c5180dcdf385be90c3d0bb
font_02_sfnt_off0001977b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1977B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1